1 track of BART Transbay service expected to resume by 4 p.m.

The Transbay Tube remains shut down this morning because of a three-alarm fire at a construction site near the West Oakland station. The fire started at 2:15 a.m. and had 100 foot flames at its peak. Arson investigators are at the scene and they believe the fire was deliberately set at the site that was being designated for low income housing for seniors. There were no evacuations and no one was hurt in the fire that destroyed the four story building.

The fire department said it took PG&E six hours to shut off the gas. Firefighters said they were standing around and waiting and could not go in to put out the hotspots because it wasn't safe. A PG&E spokesperson said they weren't allowed in because the fire department kept them out because of fire concerns.

A BART official said the problem is electrical and there is no structural damage to the running rail or the concrete structure that supports the track.

BART has asked for mutual aid from other transit agencies to provide bus service to cross the Bay. AC Transit buses are picking up displaced BART riders for free, but long lines have formed in several locations in Oakland, with some commuters waiting more than an hour and a half to board a bus.

Ferry service has not been free for commuters, but has been busier than usual.

Traffic was backed up for miles headed to the Bay Bridge and was impacted even more by a motorcycle crash earlier this morning.

Arson investigators are asking for the public's help with who set the fire, if you know anything please call (510) 238-4031.

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