OAKLAND (CBS SF) — A failure of the air compressors on two new BART cars forced the underground evacuation of 421 passengers from a stalled train earlier this week, officials announced Thursday.

BART spokeswoman Alicia Trost said once the air compressors failed, the Fleet of the Future train could not be moved.

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“While we are still investigating, our preliminary finding is that we had two adjacent cars on the train that had their air compressors malfunction causing a failure of train line communication between the cars,” she said. “This resulted in the train failing in a safe mode and being rendered unable to move.”

Trost said once the passengers had been trapped in the darkened underground tunnel in Oakland for an hour officials “made the decision to evacuate” the train.

“This is the first time we have had a failure of this nature on the new cars,” she said. “We are analyzing the failure and determining if any modifications are needed to the cars.”

BART said 421 people had to be evacuated from the disabled train. No one was injured during the evacuation.

“Because 12th Street was so close, it was decided we would have them walk from the train – the few hundred feet to the platform because that was the fastest way to get them out of the train and on their way,” said BART spokesperson Anna Duckworth.

Passenger Jeff Estrellanes was part of the evacuation.

“I was all of a sudden thrown back into my seat. I stood up and I was thrown back into my seat – it’s almost like someone unplugged the electric from the BART train,” said Estrellanes. “That’s when the waiting began…followed by the walking.”

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He said he was 2 hours late for work.

“At the end of the day, I’m just more disappointed than anything. We get increased rates and increased parking fees and then this happens. I’m hoping they can fix whatever went wrong and prevent stuff like this from happening,” said Estrellanes.

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