UPDATE - US: Three people injured in YouTube HQ shooting

ADDS DETAILS THROUGHOUT

By Michael Hernandez

WASHINGTON (AA) - Police confirmed Tuesday that they are responding to an active shooter at YouTube's California headquarters.

Brent Andrew, with San Francisco General Hospital, described the shooting as a "multiple casualty" event.

Three people are being treated for injuries at the hospital. Two of the victims are female while one is male, he said. The 36-year-old male is in critical condition while one woman is in serious condition and the other is in fair condition.

The San Bruno Police Department urged people to stay away from the building, located at Cherry Ave and Bay Hill Drive.

Earlier, several YouTube employees posted on social media that they heard gunshots and took cover inside before fleeing the building.

"Active shooter at YouTube HQ. Heard shots and saw people running while at my desk. Now barricaded inside a room with coworkers," YouTube employee Vadim Lavrusik wrote on Twitter before saying he was evacuated.

Media footage of the scene showed massive groups of people being escorted out of the corporate headquarters amid a heavy police presence.

Several media reports have indicated the suspected shooter is female.

Google, the parent company of YouTube, said on Twitter it is coordinating with authorities and will post additional information as it becomes available.