(SAN FRANCISCO) -- Two Bay Area Rapid Transit (BART) workers were killed after being struck by a train on Saturday, just one day after BART union workers walked off the job. The fatal strike happened on Saturday afternoon outside of San Francisco in the town of Walnut Creek, Calif. "This is a tragic day in BART's history," BART's General Manager Grace Crunican said in a statement.
"The entire BART family is grieving. Our thoughts and prayers are with the family and friends of our deceased co-workers. This accident is under investigation. All the proper authorities have been notified."
Police are still investigating the accident, and the National Transpiration Safety Board has dispatched two investigators to the area to examine the accident as well. The deaths are the just the sixth and seventh deaths recorded in BART history.
According to BART officials the train was out of operation and transporting workers and the two workers struck and killed were investigating a dip in the tracks. One of the workers was a union employee and the other was a contractor. Neither of those killed have been identified.
"Both people had extensive experience working around moving trains in both the freight train and the rapid transit industry," BART officials said in a statement.
Officials said the train was in automatic mode at the time of the strike, meaning no engineer was directly at the controls. In a statement BART officials said an "experienced operator" was at the controls at the time of the accident.
Paul Oversier, head of BART operations, called the accident, "a tragedy of the greatest proportion."
Oversier said that multiple BART employees were riding the train at the time of the accident, although they did not specify who was in control of the train. Oversier also said the two workers on the tracks would be expected to be able to clear "the operating envelope within 15 seconds of when a train gets to their location."
"We are saddened to learn that two BART employees were killed today after being hit by a BART train," Patricia Schuchardt, president of the union AFSCME 3993, said in a statement. "One of the employees was a member of AFSCME Local 3993. Our hearts go out to the family of both workers as well as to the person operating the train. This is a tragedy."
The Union is not picketing BART stations on Sunday out of respect for the workers.
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