SAN FRANCISCO (CBS SF) – A search was underway for a driver who jumped off the San Francisco/Oakland Bay Bridge after a multi-car crash that prompted the shutdown of westbound lanes for almost an hour.

All lanes have been reopened, but according to the California Highway Patrol, the U.S. Coast Guard is still searching for the individual.

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The crash near the center anchorage, just west of Treasure Island was reported at 6:56 p.m., according to the CHP.

A Sigalert was issued just after 7 p.m., saying multiple lanes were blocked just west of Treasure Island.

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One of the vehicles involved may have been a UPS truck, according to the CHP.

Motorists were advised to expect delays and to use alternate routes.

The Sigalert was cancelled at 7:57.

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This investigation is ongoing.