East Japan Railway Company (JR East) reported that train services on the Yamanote Line, in both clockwise and counterclockwise directions, as well as the Keihin-Tohoku Line, were suspended starting from the first train this morning (16 Jan). This caused chaos for tens of thousands of commuters heading to work, as the Yamanote Line is a vital route connecting key districts such as Shinjuku, which sees up to 3.5 million daily users.
JR East stated that the power outage began at about 03:50 near the power supply station serving the area between Shinbashi and Shinagawa stations in central Tokyo.
Initially, there was a scheduled nighttime power cut for infrastructure upgrades at Tamachi Station, but officials were unable to restore the electrical system before the first trains started running. Additionally, at around 08:00, a fire was reported at a power station near Tamachi Station; firefighters took approximately 90 minutes to bring the blaze under control. Authorities are still investigating whether the fire and the power outage are directly related.
NTV television broadcast footage showing passengers on Keihin-Tohoku Line trains stranded between stations gradually disembarking and walking along the tracks toward safe areas, with firefighters and railway staff closely assisting them.
JR East now expects to resume normal train operations around 13:00 local time after completing safety checks and restoring the electrical system.
This incident caused widespread delays because the affected routes serve as major arteries linking transportation hubs like Tokyo and Yokohama stations, which are among Japan's most densely populated business and residential areas.