A Yokohama Municipal Subway Blue Line train departing Shimoiida Station derailed early Thursday morning with about 130 people on board. No injuries were reported.
The first train of the day went off the tracks at about 5:25 in the morning shortly after departing Shimoiida Station in the city's Izumi Ward.
A train driver noticed the train, consisting of six cars and bound for Azamino Station, had derailed immediately after leaving Shimoiida Station and contacted the subway's command center, according to city officials.
The train traveled for about 40 meters from the station before the driver stopped it by applying the emergency brake. Of the six cars, five came off the rails. The passengers walked through the tunnel and back to Shimoiida Station, the officials said.
Citing city officials, public broadcaster NHK reported that temporary tracks were placed on top of the regular tracks to allow a work train to operate overnight. The officials said workers apparently forgot to remove the temporary track, which caused the train to run onto it and derail.
All train services were temporarily suspended on the Blue Line, but partially resumed later.
Upon returning to the station, passengers asked station personnel about alternative routes, with many directed to a nearby station operated by Sagami Railway, also known as Sotetsu.
"It will take longer than usual to get to the office," said a 43-year-old office worker who appeared to be perplexed.
