Bay Area Rapid Transit officials are trying to determine the cause of a train derailment on New Year's Day in the East Bay.
BART said it is examining why its operations control center lost communication with the interlocking system that allows the trains to switch tracks.
"The operations control center was unable to communicate with the interlocking to move the tracks into the proper position, so they instructed the train operator to stop the train, off board, and manually crank the tracks into position," BART spokesman Jim Allison said. "This is a procedure that they're trained to do, that they practice, and it's not entirely uncommon to do it."
Crews late Monday worked to clear the train that derailed earlier in the morning between the Orinda and Lafayette stations. BART said it was "hopeful to have at minimum, single tracking train service through the area on the Yellow line for morning service. It could be full normal service depending on progress made."
Two lanes of Highway 24 were also shut down to allow a large crane to work on re-railing the train. At 7:10 p.m., BART reported the crane was able to re-rail both impacted cars. The cars will be towed out of the area and to a yard.
BART said late Monday track crews were making repairs to the damaged sections of the track.
The partial derailment of the eastbound yellow line train happened shortly after 9 a.m. just outside the Orinda station. Nine people were transported to medical facilities to be evaluated, but none of their injuries were considered to be major, according to BART.
Two train cars reportedly caught fire, BART said. Orinda firefighters extinguished the flames.
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Passengers on the train were safely evacuated and escorted to the Orinda station by BART personnel, the transit agency said.
"It's the first day of the year. You don't expect anything crazy," BART rider Lia Burrell said.
Burrell and her friends were riding BART back to Antioch when the train derailed and caught fire, forcing them to jump off the train and run.
BART train service between Rockridge and Walnut Creek was also suspended while crews worked to rerail the train and fix any damages.
A bus bridge was set up and provided full service between the Rockridge and Walnut Creek stations in both directions, BART said.
Other BART lines were not affected by the incident.
"Once an investigation is complete it will confirm all the details of the incident," said Debora Allen, board director for BART. "We believe this actually was a human error and not some malfunction of our equipment."