2025 Den-en-toshi Line train collision

2025 Den-en-toshi Line train collision
The Tokyu 5000 series (set 5101), which derailed and was damaged in the collision
Details
Date	5 October 2025;8 days ago (2025-10-05) approximately 11.00 p.m. (JST)
Location	Near Kajigaya Station
Coordinates	35°35′37″N139°36′21″E / 35.593699°N 139.605846°E / 35.593699; 139.605846
Country	Japan
Line	Den-en-toshi Line
Operator	Tokyu Railways (Tokyu Corporation)
Owner	Tokyu Group
Incident type	Collision, leading to train car derailment
Cause	Signal setting error
Statistics
Trains	Tokyu 5000 series Tokyu 2020 series

On 5 October 2025, a passenger train with 149 passengers collided with an out-of-service train near Kajigaya Station in Kawasaki, Kanagawa Prefecture, Japan, on the Den-en-toshi Line. The collision damaged both trains and caused one of the trains to derail. The incident occurred shortly after 23:00 local time, and train services on parts of the line were suspended for about 25 hours. The incident affected approximately 652,000 passengers and 1,107 train services, including the Ōimachi Line that runs through services. ^{[1] [2]}

Background

Kajigaya Station is served by the Den-en-toshi Line, which links central Tokyo to the suburban Kanagawa Prefecture area. Prior to the incident, Tokyu Corporation had conducted repair work on signal systems at and near the station. Following the collision, the operator disclosed that a "signal-setting error" had persisted for years since maintenance works were carried out in 2015. ^[3]

Incident

The collision occurred when the rear car of an out of service Tokyu 5000 series (set 5101) was struck by an oncoming Shibuya bound Tokyu 2020 series train (set 2035) as it was entering a layover track. The impact caused the out of service train to derail. It was hosting a trainee driver under instruction and had reportedly stopped slightly ahead of its designated position, leaving part of the train protruding onto the active track. ^[4] The collision caused visible damages but no serious injuries were reported among the 149 passengers on board the moving train or among the crew on the stationary train. ^[4]

Aftermath

Following the collision, normal services on the Den-en-toshi Line were disrupted for a few days while recovery and safety inspections were conducted. Tokyu Railways deployed maintenance crews to remove the derailed 5000 series car (set 5101) and to inspect track and signal equipment near Kajigaya Station. ^[5]

Preliminary investigations found that the out of service train was 19 meters out of position. ^[6] The Japan Transport Safety Board (JTSB) dispatched investigators to the site on 6 October to collect onboard data recorders, examine the signal interlocking system and interview operating staff. ^[7]

References

1. Murakami, Junji; Somedaya, Ryuta; Kano, Kohei (6 October 2025). 田園都市線で列車衝突、けが人なし　一部不通、始発からダイヤ乱れる [Train collision on Den-en-toshi Line, no injuries, partial service outage, timetable disrupted from first train]. The Asahi Shimbun (in Japanese). Archived from the original on 5 October 2025. Retrieved 5 October 2025.
2. Atsuhiko, Kimura; Toru, Shirakawa (7 October 2025). 田園都市線と大井町線が運転再開　計1107本運休、65万人に影響 [Den-en-toshi Line and Oimachi Line resume operations, with a total of 1,107 trains cancelled, affecting 650,000 passengers]. Mainichi Shimbun (in Japanese). Archived from the original on 7 October 2025. Retrieved 7 October 2025.
3. "Tokyu says train collision caused by signal setting error". japantimes.co.jp. The Japan Times. 7 October 2025. Retrieved 13 October 2025.
4. "Overnight train collision near Tokyo causes long delays for commuters". english.kyodonews.net. Kyodo News. 6 October 2025. Retrieved 13 October 2025.
5. "Train collision causes derailment in Kawasaki, southwest of Tokyo". ntv.co.jp. Nippon Television Network System. 7 October 2025. Retrieved 13 October 2025.
6. "Derailed Train in Tokyo was 19 Meters Out of Position; 650,000 Passengers Affected by Suspended Service". japannews.yomiuri.co.jp. The Yomiuri Shimbun. 7 October 2025. Retrieved 13 October 2025.
7. Inoue, Yukana (6 October 2025). "Den-en-toshi Line trains collide, halting service". japantimes.co.jp. The Japan Times. Retrieved 13 October 2025. Two members of the Japan Transport Safety Board have been assigned to investigate the case.

External links

• "Train collision causes derailment in Kawasaki, southwest of Tokyo" on YouTube