PLEASANT HILL (CBS SF) — BART officials are saying that repairs to a damaged train, track and third rail following a derailment at the Concord BART station Friday evening are likely to continue through Saturday night.

Train service past Pleasant Hill on the Pittsburg/Bay Point line has been canceled, with buses serving the Concord, North Concord/Martinez and Pittsburg/Bay Point stations from Pleasant Hill until the end of scheduled service, BART said in a statement Friday evening.

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Riders traveling in to San Francisco or Oakland are being advised to catch their trains at the Pleasant Hill station on Saturday. A shuttle train will also be operating between Pittsburg/Bay Point and North Concord, and buses will operate between the North Concord, Concord and Pleasant Hill stations.

The out-of-service train, which was traveling empty to the Concord Yard, was just leaving the Concord station around 6:30 p.m. when some train wheels went off the track, BART officials said.

“To me, it sounded like it was just going way too fast,” Adam Goemar, an eyewitness, told KPIX 5. “It sounded like a train out of control.”

“Saw it kind of bounce. Saw some sparks flying out from underneath it. And then, all of a sudden it just went sideways, saw the smoke pouring out from over the top,” Goemar said.

While the cause remains unknown, the derailment occurred as the train traveled over a switching mechanism known as an interlocking, BART spokeswoman Alicia Trost said.

The train is now blocking the rails in both directions and removing it is expected to be a difficult, lengthy process.

The train operator was not injured and no passengers were on board. Goemar told KPIX 5 that he saw the operator scramble off the train unhurt.

Roberta Lamark, 50, was heading back from work in Berkeley when BART officials notified passengers that there had been a derailment just ahead.

Lamark took a shuttle bus from Pleasant Hill to Concord and was waiting for more than an hour to be picked up by her husband to get home to Antioch.

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“It was terrible, just chaos,” she said. “You have to count your blessings though, because we were right behind it.”

The incident drew dozens of curious residents to the scene.

Davina Hunter lives nearby and came out with her dog to see the train after hearing media helicopters overhead.

“This just shows we need more upgrades,” Hunter said.

Susan Sunshine, 57, also lives nearby and joined the crowd at Concord to see the derailed train.

She said she was considering having her family get on BART at Pleasant Hill now instead of Concord.

The Concord station was also the scene of a derailment on March, 13, 2011 involving a 10-car train carrying 65 passengers to San Francisco International Airport. Three people reported minor back injuries after that incident.

“It definitely is something we worry about,” Sunshine said.

Service in the 2011 incident was restored in less than 24 hours.

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