SAN FRANCISCO (CBS SF) — Two people were critically injured early Sunday in a crash in the westbound lanes of the San Francisco-Oakland Bay Bridge.

San Francisco firefighters said emergency crews responded to reports of a crash on the bridge west of Treasure Island shortly after midnight.

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The crash quickly shut down four westbound lanes, backing traffic up into San Francisco.

Arriving emergency workers found two injured crash victims, one of whom was trapped inside a vehicle and the jaws of life were used to free them.

Both were transported to the hospital in critical condition. There was no immediate update on their condition Sunday morning.

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No other information was available on details of the crash or if alcohol or drugs played a role in the collision.