By Joe Vazquez

SAN FRANCISCO (KPIX 5) — San Francisco Police investigators are leaning toward a mechanical issue as the cause of Friday’s tour bus crash in Union Square that injured 20 people, a top police official tells KPIX5.

“It appears to be a mechanical defect with the vehicle itself,” said San Francisco Supervisor Jane Kim, who said she received a preliminary report directly from police.
Kim said there were other problems as well.

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“I think there are questions about how the recordkeeping has been kept, and also how, you know, how vehicles are being maintained by many of these very large tour bus companies regulated by the state,” Kim said.

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Video of the crash will be crucial to the investigation, and many stores in Union Square captured footage of the crash in progress, the police official told KPIX 5.

The California Highway Patrol is now reviewing the bus’s maintenance records.

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Kim is calling for changes in state law that would allow local governments to regulate tour bus maintenance.