Officials with the transit agency say it happened at about 6:20 p.m. Friday when a Pittsburg/Bay Point train was headed back to the Concord yard.
The Concord, North Concord/Martinez and Pittsburg/Bay Point BART stations are closed and there is currently no service beyond Pleasant Hill.
According to BART spokesperson Alicia Trost, people will not have BART service past the Pleasant Hill BART Station tonight, all day Saturday and throughout Saturday night.
BART has set up a bus bridge for affected passengers at the closed stations and it will run throughout Saturday. However, Trost said people should plan ahead that they will not have BART service on Saturday. If people need to catch a BART train, they should go directly to the Pleasant Hill station.
Trost said the reason this repair will take a long time is because they need to repair the damage done to the track and the third rail.
"This train was just ending its run, like it normally would. It was heading back to the yard as it normally would every day. There was no particular reason it was being sent out of service. It was just at the end of its service for the day. The train operator was pulling the train out of the Concord station and as it passed over an interlocking, which is what makes trains go from one track to another, several of the wheels came off the track," said Trost.
There are no reports of injuries.
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