There were reports of a possible fire on a train that caused the equipment to fail. But after investigation, BART says there was no fire occurred on the train.
A photograph taken by BART passenger Charla Rodney shows smoke coming out of the train.
The incident happened at around 2:30 p.m. between the MacArthur and 19th Street BART stations.
All passengers have safely been evacuated.
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As of 4:22 p.m., normal train service has been restored through MacArthur station, but residual delays were expected in downtown Oakland in the Antioch, Berryessa, Richmond and San Francisco directions.
BART said the cause in an Initial finding is connected to a collector shoe, a piece of equipment on each car that interfered with the third rail causing smoke.
BART said it wasn't a fire, but can look like one.