SAUSALITO (CBS SF) – Several dozen students headed for the Urban School in San Francisco were temporarily stranded on Highway 101 in Marin Tuesday morning after their school bus driver noticed smoke coming from the engine during the drive from San Rafael.

The driver pulled to the side of Southbound Highway 101 just before the Waldo Tunnel and ushered all of the teens behind a guard rail.

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Using a fire extinguisher making sure the smoke didn’t get out of control.

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The students on board were transferred to another bus without incident, according to the CHP.

The cause of the fire is under investigation.

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