Facebook Inc. buildings in the Silicon Valley town of Menlo Park were evacuated after a bomb threat.

A bomb threat unit was on the scene, searching a building in the 200 block of Jefferson Drive, the Menlo Park Police Department said in a statement. The headquarters of Facebook-owned Instagram is on that block.

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A Facebook spokesman said a few buildings were evacuated, but all employees are safe. The company will send further updates once the situation is clearer.