CS gas has been used in spray form by many police forces as a temporary incapacitant and to subdue attackers, persons, or civil protestors. Officers who are trained in the use and application of CS spray are routinely exposed to it as part of their training. It has also been used in criminal attacks in various countries. [1] [2] [3] [4]
Use of CS in war is prohibited under the terms of the Chemical Weapons Convention, signed by most countries in 1993 with all but five other states signing between 1994 and 1997. The reasoning behind the prohibition is pragmatic: use of CS by one combatant could easily trigger retaliation with much more toxic chemical weapons such as nerve agents. Only five countries have not signed the Chemical Weapons Convention and are therefore unhindered by restrictions on the use of CS gas: Angola, Egypt, North Korea, Somalia, and South Sudan. [5] [6]
CS gas was used extensively by Bahrain's police from the start of the Bahraini uprising. [7] : 260 The Bahrain Independent Commission of Inquiry concluded that Bahrain's police used a disproportionate amount of CS gas when dispersing protests, and that in some situations, police fired CS gas into private homes in an "unnecessary and indiscriminate" manner. [7] : 277 In one particular incident witnessed by Commission investigators, police fired "at least four tear gas canisters (each containing six projectiles) ... from a short range into the kitchen and living room of a home." [7] : 261
According to opposition activists and families of the dead, ten individuals died as a result of CS gas between 25 March 2011 and 17 December 2011. [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] One allegedly died from the impact of the CS gas canister, [13] and the remainder are said to have died from the effects of inhaling the gas. The Bahrain Independent Commission of Inquiry received information that a further three deaths may have been attributable to the use of CS gas. [7] : 239–40, 253 Of these three, one allegedly died from the impact of the canister, and two from the effects of inhaling the gas.
The Canadian Forces exposes basic training candidates to CS gas as part of gas mask training and drills. This training continues in subsequent career stages. Many law enforcement agencies also use CS gas as a riot control device. Since 2008, the SPVM police force in Montreal has increased its use of CS Gas for crowd control, although Police policy is to only use it as a last resort.[ citation needed ] Several incidents where protesters have been seriously injured by having CS gas fired at them from point-blank range have raised concerns about the methodology and training of Officers in the Montreal Riot Squad, particularly in relation to "Use of Force". [18]
Tear gas is routinely used in Chile by Carabineros, to disrupt civilian protests. [19] During the 2019 uprising the use of expired gas has been reported, prompting Carabineros to say that "they are like yogurt expired 5 days ago, it doesn’t damage people". [20]
Peru Police forces spray CS gas in riot control situations.
CS was first tested in the field by the British army in Cyprus in 1958. At this time it was known by the code name T792. [21]
CS has been widely used by Egyptian Police/Military Forces from January 2011 onwards.
The Police Tactical Unit of the Hong Kong Police Force used 87 rounds of CS projectiles (both riot gun launched and hand thrown) in Hong Kong on 28 September 2014 against thousands of protesters obstructing major thoroughfares in Hong Kong 2014 Hong Kong protests, also known as the Umbrella Movement.
The CS gas canisters and content used were purchased by the Hong Kong SAR Government from CHEMRING, a British weapons manufacturer. The crowd used umbrellas to fend off the gas, which was often ineffective. Apart from the HK police, CS gas spray is also used by Witness Protection and Firearms Section of Independent Commission Against Corruption (Hong Kong).
From 12 June to 4 August 2019, police used 1000 tear gas canisters. Then, on the single day of 5 August, police fired more than 800 tear gas canisters in their operations throughout almost every district of the city. [22] In one instance, a tear gas canister was deployed indoors, in Kwai Fong station during a march, on 11 August 2019. The police initially denied the incident. [23] In defense, protestors are seen picking up tear gas cans with thick gloves to throw them back or to extinguish them in sealed water containers. [24]
Up to 22 October 2019, over 5000 made-in-China tear gas canisters have been deployed by the Hong Kong Police Force. Canisters marked with dates overdue have been collected in many occasions. It is unpredictable for the potential hazards to the Hong Kong environment and living conditions. Recent massive deaths of fish around Hong Kong seas was also suspected to be one of the consequences.[ citation needed ] Many birds were found dead in the Chinese University of Hong Kong, after 12 November that the riot police fired over 2000 tear gases towards the campus. [25] A Hong Kong journalist, Chan Yu-hong from the Stand News declared he was diagnosed with chloracne (by a Traditional Chinese physician instead of a physician [26] ) after exposure to made-in-China tear gas while covering the 2019 Hong Kong protests.
The overuse of tear gas has been one of the concerns in the anti-extradition bill protests.
Iraq successfully developed CS during the 1970s and during the 1980s produced tons of the substance firstly at Salman Pak and later at al-Muthanna. [27]
Blackwater Worldwide, acting as an agent of the United States, deployed CS in the Iraq War from a helicopter hovering over a checkpoint in the Green Zone in Baghdad. [28]
Israel Police forces spray CS gas in riot control situations. It is widely used at demonstrations within the Palestinian Territories and at the Israeli West Bank barrier. [29] [30]
Palestinian Authority forces used CS gas against protesters in Ramallah on June 26, 2021 [31] and against rioters in Nablus in September, 2022. [32]
CS tear gas was used in suppression of the mutiny in Makati that was led by Sen. Antonio Trillanes. The tear gas was fired in the building and all the people in the building including reporters were affected. [ citation needed ]
The Gendarmerie of Bucharest used large quantities of CS gas against civilians during the protests of 10 August 2018 in Bucharest. [33]
Russia developed in the late 1970s a K-51 grenade for riot control and for other tactical operations. The K-51 burns for 16 seconds, producing a thick CS smoke. [34] Reportedly used in the Donetsk region of Ukraine in 2015, it has been reported in use again in the 2022 Russian invasion of Ukraine, being dropped by drones [35] and in Ukraine in 2024. [36]
Tear gas is not commonly used in Spain but it has been used some times to disrupt civilian protests by the Policia Nacional and Mossos d'Esquadra in Catalonia. [37]
The LTTE, also known as Tamil Tigers of Sri Lanka, an insurgent group in Sri Lanka used CS gas against government forces in September 2008. [38] Its use hindered the army's progress but ultimately proved ineffective in preventing the army from overrunning LTTE positions.
This is one of the few cases of insurgents using CS gas.
Sudanese forces extensively used CS gas during the latest wave of demonstrations began in 2018. [39] The use of CS gas fired through rifles or hand grenades is not exclusive to police forces but is widely used by non-trained militia to suppress protesters movement and to intimidate civilians by firing blindly into neighborhoods and homes. [40] CS gas canisters are generally used also as a ballistic weapon and aimed at the faces of protesters to cause serious body and head injuries. [41] Some death cases were recorded due to choking on tear gas because of excessive use in confined areas. [42]
CS gas was used extensively in the Bogside area of Derry, Northern Ireland during the "Battle of the Bogside", a two-day riot in August 1969. A total of 1,091 canisters containing 12.5g of CS each, and 14 canisters containing 50 g of CS each, were released in the densely populated residential area. [43] On 30 August the Himsworth Inquiry was set up to investigate the medical effects of its use in Derry. Its conclusions, viewed in the political context of the time, still pointed towards the necessity of further testing of CS gas before being used as a riot control agent. During the rioting in Belfast, the following year, known as the Falls Curfew, the Army fired up to 1,600 canisters into the densely populated Falls Road area. It was also used in Lenadoon on 9 July 1972 on the breakdown of the IRA ceasefire. Not long after, the British Army and Royal Ulster Constabulary ceased using CS in Northern Ireland.
CS gas has not been routinely deployed on the British mainland. It has seen use in rare cases. [44] The first use of CS gas on the UK mainland that was not part of military training was carried out in 1944 during a hostage siege at a north London address. Soldiers were asked to throw CS grenades through the skylight in hope of bringing the incident to a speedy conclusion, but the hostage-taker had brought his civilian-issue gas mask with him, negating the effect.[ citation needed ] The siege of Trough Gate 1973 in Oldham was the second non-military use of CS gas on the UK mainland. During a four-hour standoff, Frank Alan Stockton shot at police but was flushed from his home with CS gas and police dogs. [45] [46] [47]
During the 1980 assault on the Iranian Embassy, SAS soldiers used CS gas contained within stun grenades to incapacitate the militants who had kept the building under siege for six days. All but one of the remaining hostages were saved and all but one of the hostage-takers were killed, with the other being taken into custody. [48]
In 1981, CS gas was used to quell rioting in the Toxteth area of Liverpool. [49] [50]
Following the 2011 England riots, there was consideration given to making CS gas, water cannon and other riot control measures available to police for use in the event of serious disorder. [51] The British Armed Forces use CS gas annually to test their chemical, biological, radiological and nuclear defense (CBRN) equipment. During initial training they introduce recruits to CS gas by placing them in a small enclosed space known as a Confidence Test Facility (CTF) and igniting chemical tablets to induce CS production. After recruits have carried out their CBRN drills, they must remove their respirators so that they are exposed to the CS for up to 20 seconds to experience its effects and become confident their respirators work. [52]
CS incapacitant spray had been used routinely by the British police since its introduction in 1996. It was issued as an item of equipment to police officers for protection and to assist in dealing with violent incidents. [44] [53] British police recruits are typically exposed to CS aerosol, in a controlled environment, as part of their basic training. [54] A six-month trial by sixteen police forces in England began on 1 March 1996. CS spray was used in the UK more than 10,000 times in the period between its introduction in 1996 and September 1998. [55] Forces began replacing CS spray with Captor or PAVA spray, [56] [57] due to its non-flammable nature. This allowed use in conjunction with Tasers, which have been rolled out more widely. As a result, CS spray is now redundant – with Captor or PAVA used by all forces. [58]
The CS spray used by police forces was in the form of a hand-held aerosol canister containing a 5% solution of CS dissolved in methyl isobutyl ketone and propelled by pressurized nitrogen. [59] The CS spray used by UK police was generally more concentrated than that used by American police forces (5% vs 1%). [60] The liquid stream is directed where the user points the canister, being accurate up to 4 metres. Police are also trained in helping the incapacitated person recover once successfully restrained. [59] Under Section 5 of the Firearms Act, CS and other incapacitant sprays are classed as prohibited weapons, making it unlawful for a member of the public to possess them. [61]
On 16 March 1996, a Gambian asylum seeker, Ibrahima Sey, was taken to Ilford Police Station in east London. Whilst incapacitating Sey, who was suffering from excited delirium, police sprayed him with CS spray and held him on the ground for approximately 15 minutes, and he subsequently died. [62] In 1999, the mental health charity MIND called for a suspension of the use of CS spray on mentally ill people until it was proved to be safe. [63] In February 2006, Dan Ford, from Wareham in Dorset, received permanent scarring to his face after being sprayed with CS during an arrest by police. Ford was subsequently advised by doctors to stay out of sunlight for at least 12 months. After the incident, his cousin, Donna Lewis, was quoted as saying, "To look at him, it was like looking at a melting man, with liquid oozing from his face." [64]
CS is used by many police forces within the United States. It was used by Federal Bureau of Investigation law enforcement officials in the 1993 Waco Siege. [65] Riot police in Pittsburgh, Pennsylvania in September 2009 used CS gas and riot control techniques to disperse assemblies in the vicinity of the 2009 G-20 Pittsburgh summit. Tear gas was used in at least 100 cities during the 2020 protests that took place in the U.S. [66] In Portland, Oregon alone, tear gas was used more than 100 times in a two-week period and there were at least two nights in which it was used more than twenty times. [67]
In Berkeley, California during the Bloody Thursday [ broken anchor ] events in the People's Park on 21 May 1969, a midday memorial was held for student James Rector, a non-protester shot and killed by police, at Sproul Plaza on the university campus. In his honor, several thousand people peacefully assembled to listen to speakers remembering his life. National Guard troops surrounded Sproul Plaza, donned their gas masks, and pointed their bayonets inward, while helicopters dropped CS gas directly on the trapped crowd. No escape was possible, and the gas caused acute respiratory distress, disorientation, temporary blindness and vomiting. Many people, including children and the elderly, were injured during the ensuing panic. The gas was so intense that breezes carried it into Cowell Memorial Hospital, endangering patients, interrupting operations and incapacitating nurses. Students at nearby Jefferson and Franklin elementary schools were also affected. [68] [69]
Members of the United States armed forces are exposed to CS during initial training, and during training refresher courses or equipment maintenance exercises, using CS tablets that are melted on a hotplate. This is to demonstrate the importance of properly wearing a military gas mask or protective mask, as the agent's presence quickly reveals an improper fit or seal of the mask's rubber gaskets against the face. Following exposure while wearing a mask, recruits are ordered to remove the masks and endure exposure in the room. These exercises also encourage confidence in the ability of the equipment to protect the wearer from such chemical attacks. Such an event is a requirement for graduation from United States Army Basic Training, Air Force Basic Military Training, Navy Basic Training, and Marine Corps recruit training. [70] CS gas in the form of grenades is also used extensively in the United States Marine Corps and United States Army in some service schools. CS gas is used during the final field exercise of the Scout Sniper Basic Course to simulate being compromised. In addition, it is used during the 25 km (16 mi) escape-and-evasion exercise ("Trail of Tears"), the last event before graduation from the course. Navy Corpsmen participating in Field Medic training in order to serve with the Marines must go through their second CS gas exercise before finally arriving at their unit. It is also used during several events in the Marine Corps Basic Reconnaissance Course (BRC) including some rucksack runs and escape-and-evasion exercises. While students going through the course are given the opportunity to bring and wear a gas mask for the event, usually none are worn because once donned, gas masks could not be removed until the end of the exercise. This could last anywhere from 3–12 hours and would make running 25 km (15 miles) while wearing 125 lb (57 kg) of gear virtually impossible.
It has been reported that thousands of tons of CS gas were used by the U.S. forces in Vietnam to bring Viet Cong into the open.[ citation needed ] It was also used by the North Vietnamese forces in some battles like Hue in 1968 or during the Easter Offensive in 1972. [71] [ failed verification ]
CS gas has been and is still routinely used by Greek riot police (MAT) in order to quell student and labour protests, as well as riots.
CS was used to quell a protest in Lusaka, Zambia in July 1997 and the 1999 WTO riots in Seattle. Amnesty International reported that it had been manufactured by the UK company Pains-Wessex. Subsequently, Amnesty called for an export ban when the receiving regime is either not fully trained in the use of CS, or had shown usage "contrary to the manufacturer’s instructions". [72]
In September 2000, the Guardian newspaper revealed how a UK company, HPP, used legal loopholes to export CS to a private security company in Rwanda, in breach of United Nations sanctions. [73] The Guardian also reported that CS was used by the Hutu militia in Rwanda to flush Tutsis out of buildings before hacking them to death.
CS has been used by the government in South Africa; by Israel against Palestinians and Israelis; by the South Korean government in Seoul, and during the Balkan conflicts by Serbia. In Malta it was used by police between 1981 and 1987 to the detriment of Nationalist Party Supporters.
CS tear gas was used at the G8 protests in Genoa, Italy [74] and Quebec City, Canada [75] during the FTAA anti-globalization demonstrations during the Quebec City Summit of the Americas.
The Malaysia Federal Reserve Unit has also been known to use CS tear gas against its citizens who rallied for clean and fair elections under what were called Bersih rallies in 2011 [76] and 2012. [77]
The Canadian, Norwegian, Dutch, Finnish and Australian Defence Forces train their personnel with CS gas in a manner similar to that of the US, as it is a basic part of CBRN (Chemical, Biological, Radiological, Nuclear) training. Gas is released by burning tablets, usually in a building reserved for this purpose (a "gas hut"). In the training, the person enters the building unprotected and must fit and clear the gas mask before leaving. Other drills such as drinking and under-mask decontamination are also practiced. Some Norwegian units are exposed to CS gas while engaged in mental and physical activity such as addressing the officer in command by stating name, rank, and troop before doing 30 push-ups. [78]
In Australia, prison officers used CS gas against five teenage boys in Darwin's Don Dale Juvenile Detention Centre in August 2014. [79]
Non-lethal weapons, also called nonlethal weapons, less-lethal weapons, less-than-lethal weapons, non-deadly weapons, compliance weapons, or pain-inducing weapons are weapons intended to be less likely to kill a living target than conventional weapons such as knives and firearms with live ammunition. It is often understood that unintended or incidental casualties are risked wherever force is applied, however non-lethal weapons minimise the risk of casualties as much as possible. Non-lethal weapons are used in policing and combat situations to limit the escalation of conflict where employment of lethal force is prohibited or undesirable, where rules of engagement require minimum casualties, or where policy restricts the use of conventional force. However, these weapons occasionally cause serious injuries or death due to allergic reactions, improper use and/or other factors; for this reason the term "less-lethal" has been preferred by some organizations as it describes the risks of death more accurately than the term "non-lethal", which some have argued is a misnomer.
Pepper spray, oleoresin capsicum spray, OC spray, capsaicin spray, or capsicum spray is a lachrymator product containing the compound capsaicin as the active ingredient that irritates the eyes to cause burning and pain sensations, as well as temporary blindness. Its inflammatory effects cause the eyes to close, temporarily taking away vision. This temporary blindness allows officers to more easily restrain subjects and permits people in danger to use pepper spray in self-defense for an opportunity to escape. It also causes temporary discomfort and burning of the lungs which causes shortness of breath. Pepper spray is used as a less lethal weapon in policing, riot control, crowd control, and self-defense, including defense against dogs and bears.
The compound 2-chlorobenzalmalononitrile (also called o-chlorobenzylidene malononitrile; chemical formula: C10H5ClN2), a cyanocarbon, is the defining component of the lachrymatory agent commonly referred to as CS gas, a tear gas which is used as a riot control agent.
Phenacyl chloride, also commonly known as chloroacetophenone, is a substituted acetophenone. It is a useful building block in organic chemistry. Apart from that, it has been historically used as a riot control agent, where it is designated CN. It should not be confused with cyanide, another agent used in chemical warfare, which has the chemical structure CN−. Chloroacetophenone is thermally stable, and is the only tear agent that is distillable at ambient conditions.
Riot control measures are used by law enforcement, military, paramilitary or security forces to control, disperse, and arrest people who are involved in a riot, unlawful demonstration or unlawful protest.
CR gas or dibenzoxazepine (chemical name dibenz[b,f][1,4]oxazepine, is an incapacitating agent and a lachrymatory agent. CR was developed by the British Ministry of Defence as a riot control agent in the late 1950s and early 1960s. A report from the Porton Down laboratories described exposure as "like being thrown blindfolded into a bed of stinging nettles", and it earned the nickname "firegas".
Tear gas, also known as a lachrymatory agent or lachrymator, sometimes colloquially known as "mace" after the early commercial self-defense spray, is a chemical weapon that stimulates the nerves of the lacrimal gland in the eye to produce tears. In addition, it can cause severe eye and respiratory pain, skin irritation, bleeding, and blindness. Common lachrymators both currently and formerly used as tear gas include pepper spray, PAVA spray (nonivamide), CS gas, CR gas, CN gas, bromoacetone, xylyl bromide and Mace.
PAVA spray is an incapacitant spray similar to pepper spray. It is dispensed from a handheld canister, in a liquid stream. It contains a 0.3% solution of pelargonic acid vanillylamide (PAVA), also called nonivamide, a synthetic capsaicinoid, in a solvent of aqueous ethanol. The propellant is nitrogen. This solution has been selected because this is the minimum concentration which will fulfill the purpose of the equipment; namely to minimise a person's capacity for resistance, without unnecessarily prolonging their discomfort.
Ali Jawad al-Sheikh was a 14-year-old Bahraini who died in the hospital on 31 August 2011 after reportedly being hit in the head by a tear gas canister shot by Bahraini security forces during the Bahraini uprising. The Bahraini government denied security force involvement in his death and offered a reward for information on the incident. Activists, however, began a series of large protests after his funeral.
The Special Tactical Contingent, nicknamed the "Raptors", commonly known as the Special Tactical Squad (STS), is a specialist riot contingent of the Hong Kong Police Force under the command of the Police Tactical Unit (PTU).
The month of August 2019 in the 2019–2020 Hong Kong protests saw a continuation of protests throughout the city. Several of the peaceful daytime protests were held by social groups such as families, the elderly, and various professions. In many instances, peaceful protests occurs during the day, turning increasingly violent at night. In North Point and Tsuen Wan, white- or blue-shirted armed groups were attacking protesters, but unlike in the Yuen Long violence of 21 July they were beaten back in North Point. Protesters aimed at drawing international attention through methods such as extended sit-ins at the airport. In many occasions, an eye injury of a female protester who had served as frontline medical staff became a symbol of the protests. At the airport protests, a mainland journalist was violently tackled by protesters who did not reveal his identity to the protesters. Protesters later apologised for this incident, reducing tensions and satisfying some pro-establishment lawmakers. The Prince Edward station attack on 31 August proved to be a further landmark event in the protests.
The conduct of the Hong Kong Police Force is a subject of controversy during the 2019–2020 Hong Kong protests. Tactics employed by the force have led to misconduct allegations and protesters have accused the Hong Kong government of using the police as a method to resolve a "lingering political crisis." Actions taken by the police force and the Hong Kong government have caused mixed reactions inside Hong Kong and in the general international community. Allegations against the police include excessive use of force, force against unspecific targets, and arrest without warrant. These allegations have been presented in various media both supporting and detracting from the complaints, such as through amateur video. In general, the spirit, rumors, videos, and other media shared by the public have caused a drop in support for the police force, and an Amnesty International report accused the police of using excessive force against civilians. One of the objectives of the 2019–2020 protests is establishment of an independent inquiry system into said allegations.
The month of September in the 2019–2020 Hong Kong protests saw again citywide unrest. Chief Executive Carrie Lam announced on 4 September that the extradition bill, in suspension since July, would be fully withdrawn, which fulfilled one of the five demands of the protesters. Also, following an earlier promise, Lam held a discussion session with randomly selected members of the public on 26 September. These acts, however, had little to no effect on the protests, as protesters insisted that all of the five demands be met. That this latter goal would be hard, if not impossible, to achieve – due to the very limited room given to Lam's administration by mainland Chinese authorities, as transpired from comments by officials – did not discourage the protesters from continuing to take to the streets.
In October 2019, the 2019–2020 Hong Kong protests saw a further escalation of violence. It became evident that the protests were unlikely to end soon, and that they posed the biggest popular challenge to Chinese Communist Party (CCP) leader Xi Jinping since his ascension to CCP general secretary in 2012. To bring the situation under control, Chief Executive Carrie Lam invoked colonial-era powers to impose an anti-mask law, aimed at preventing protesters from hiding their identity. Observers considered the law, which came into force on 4 October, as a precedent for possible wider use of emergency powers at the expense of citizens' freedoms and in addition democratic rights, as they even saw the possibility of the upcoming District Council elections being cancelled based on the emergency law. The mask ban did, however, not achieve the desired effect, but rather proved a further focal point of protests. In November, the High Court ruled the mask ban to be unconstitutional, although in April 2020, an Appeal Court ruled that it was constitutional in the case of unlawful assemblies.
The month of November 2019 in the 2019–2020 Hong Kong protests started with protesting in malls and police getting into homes and malls to arrest protesters. The death of Chow Tsz-lok in Sheung Tak, Tseung Kwan O had led to more protests. In mid November, there were city-wide strikes which lasted for more than a week. Hong Kong Police officers fired tear gas in Chinese University of Hong Kong (CUHK), Hong Kong Polytechnic University (PolyU), and nearby areas. In late November, the District Council elections were held. The pro-democracy camp in conjunction with the localist groups got more than 80 per cent of the seats and gained control of 17 out of 18 District Councils.
The 2019 CUHK campus conflict, also known as the siege of the Chinese University of Hong Kong and Chinese University of Hong Kong conflict, was a part of the 2019–2020 Hong Kong protests. As protesters disrupted traffic to facilitate a general strike on 11 November 2019, other protesters inside Chinese University of Hong Kong (CUHK) threw objects onto railway tracks near the University station, to which the Hong Kong Police Force responded by shooting pepper bullets at students and launching volleys of tear gas into the campus. The next day saw various clashes and skirmishes between the two sides, with the police storming into campus to conduct arrests while the protesters, in response, threw petrol bombs. After nightfall, the university's vice-chancellor and president Rocky Tuan arrived to seek mediation with the police, who refused to negotiate. The conflict escalated into widespread protests in various parts of Hong Kong in an attempt to divert the police's attention. At least 119 students were injured.
The 12 June 2019 Hong Kong protest, also known as "612 incident". refers to an incident of intense confrontation between anti-extradition bill protesters and the Hong Kong Police Force, occurring on 12 June 2019 outside the Government Headquarters in Admiralty, Hong Kong Island. The protest was sparked by the government's introduction of the controversial Fugitive Offenders amendment bill, which was set to go through second reading on 12 June despite mass opposition.
The siege of the Hong Kong Polytechnic University occurred during the 2019–2020 Hong Kong protests on the campus of the Hong Kong Polytechnic University (PolyU).
After the rapid deterioration of the overall situation in the city in the course of the previous months of the 2019–2020 Hong Kong protests, a degree of calming of the protests occurred in December 2019. This was due to several factors. One was an initial expectation of the protesters and their supporters that the government would finally offer concessions on the Five Demands – apart from the withdrawn extradition bill – after the resounding defeat of the pro-establishment camp in the District Council Elections on 24 November, which had dealt a blow to government rhetoric about its public support. The mass protests on 8 December were largely an expression of dissatisfaction that these concessions had not been forthcoming. Another factor seen as responsible for the decrease in the size of the protests was that the arrests during the Siege of Polytechnic University had thinned the ranks of the protesters.
This is a timeline of events in April 2020 surrounding the 2019–2020 Hong Kong protests. The COVID-19 pandemic had caused a decline in the number and scale of the protests, although the Hong Kong government, police and protesters expected that with signs of the pandemic beginning to ease in Hong Kong, major protests of the kind the city had seen before the pandemic would again erupt in summer. Most protest-related activities happened online, especially on games like Animal Crossing. This resulted in a ban on the sale of Animal Crossing in China. Hong Kong police arrested 15 Democrats on the morning of 18 April, citing their alleged participation in "unlawful" gatherings that had taken place in August and October 2019 in the context of the protests. This drew international condemnation, with accusations being made that the crackdown had been carried out at the behest of the Chinese central government, and taken advantage of many Western democracies being severely hit by the pandemic, hampering their response.
'Discharging indoors leads to panic, can lead to stampede, and at its worst it can lead to dire health consequences, including death, if people cannot escape the suffocating effects of the gas,' said Michael Power, a civil rights lawyer based in South Africa who specializes in protests and policing.
... Ukraine says its troops have faced mounting chemical attacks in recent months. The Reuters news agency reported earlier this year that Russian forces had used grenades loaded with CS and CN tear gases. The report added that at least 500 Ukrainian soldiers have been treated for exposure to toxic gases, and that one had died after suffocating on tear gas.
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