Update I

There is no longer a threat to people in the area.

NBC News is reporting that the female suspect is deceased on scene, a firearm was recovered, and the number of victims is unknown.

Update II

At 12:46 pm, 911 calls were received about gunshots on the YouTube campus. Law enforcement arrived on scene at 12:48 pm. There is one female deceased on scene. It has yet to be confirmed if the deceased individual is the shooter, but is believed to be the suspect. The suspected shooter died from a self-inflicted gunshot wound. Four other victims were transported to nearby hospitals, and one is said to be in critical condition.

** Original Post **

There are reports of an active shooter at YouTube Headquarters in San Bruno, California. YouTube employees have evacuated the building, and hospitals are receiving employees who sustained gunshot wounds.

A YouTube employee tweeted out his experience as shots rang out.

According to a CBS News anchor, an eyewitness said the shooter started at a party on the YouTube campus.

Some local stations are reporting information about the potential shooter, but the reports have yet to be confirmed.

This article will be updated as more information is released.