Facebook HQ Placed In Lockdown After 'Threat'
An apparent threat against Facebook's California headquarters has been dismissed by police after the campus was placed on a precautionary lockdown.
Staff were prevented from going home for almost 90 minutes until 8:30pm local time (0330 GMT) while officers investigated.
More than 6,000 people work for the social media giant but it was unclear how many were at the headquarters at that hour.
The site - at Menlo Park in the San Francisco area - was searched before the authorities decided the threat was "totally not credible".
Menlo Park Police Department spokesman Dave Bertini said Facebook personnel held employees inside.
"It was a totally not credible, unsubstantiated threat," he told reporters.
The spokesman declined to say what the nature of the incident was.
"I'm not even sure that it was specifically to the Menlo Park campus of Facebook," he added.
Facebook declined to comment.
The incident happened just a week after Facebook said it would pay to fund a full-time police officer to bolster security in the area around its HQ - a move seen as the first such partnership between a private company and police.
The company's offer to pay $200,000 (£120,000) annually for a minimum of three years was backed by the city council.
Ray Mueller, the Menlo Park mayor, shrugged off suggestions that Facebook could get special treatment, saying: "The only way you'd have a conflict of interest is if someone tried to exert influence over our police force.
"That's not going to happen."
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