Two federal law-enforcement officials told ABC News that early indications point to the shooting being the result of a domestic situation. They say the incident does not appear to be terror-related.
Two law enforcement sources say authorities have preliminarily identified the shooter as Nasim Aghdam, with previous addresses in both Riverside and San Diego.
San Bruno Police confirmed on Twitter that they were responding to an active shooter situation, advising people to stay away from Cherry Avenue and Bay Hill Drive.
Officers discovered one victim with a gunshot wound when they arrived and then found the shooter with what appeared to be a self-inflicted gunshot wound several minutes later, San Bruno Police Chief Ed Barberini said. He said two additional victims were later located at an adjacent business.
An employee posted on Twitter that he was barricaded inside the building before successfully being evacuated.
Active shooter at YouTube HQ. Heard shots and saw people running while at my desk. Now barricaded inside a room with coworkers.— Vadim Lavrusik (@Lavrusik) April 3, 2018
Safe. Got evacuated it. Outside now.— Vadim Lavrusik (@Lavrusik) April 3, 2018
Sister station KGO in San Francisco's SKY7 was over the scene, where law enforcement officers were seen approaching the building with guns drawn. Employees were seen being evacuated with arms overhead, with the campus flanked by dozens of police cars and emergency vehicles. Officers patted down people to make sure none had weapons.
Stanford Health Care said they were treating four to five patients, but they did not offer additional details. San Francisco General Hospital also confirmed it received three patients, and spokesman Brent Andrew said a 36-year-old man was in critical condition, a 32-year-old woman was in serious condition, and a 27-year-old woman was in fair condition. It appears the additional injuries may have resulted from the chaos that ensued after the shots rang out.
The victim in critical condition is believed to be the intended target.
The hospital said later that it did not expect to receive more patients.
Law enforcement sources tell ABC7 said the shooter was found dead in the same room as a victim.
Google, which owns the world's biggest online video website, posted on Twitter that the company is coordinating with authorities. About 1,700 people work at the campus.
Will Hudson said his friend who works for YouTube texted him about the shooter.
"I think there might be a shooter in my building," read one text. "The fire alarm went off so we started to evacuate and then people (started) running saying there was a shooter."
Hudson said his friend has made it safely back to San Francisco and is in contact with his family. Hudson said he's become accustomed to hearing about such violence but has never been so close to it before.
"It just feels strange," he said. "It feels like it could really be anyone. That's really the strangeness of it."
YouTube employee Dianna Arnspiger said she was on the second floor when she heard gun shots, ran to a window and saw the shooter on a patio outside.
She said the woman wore glasses and a scarf and was using a "big huge pistol."
"It was a woman and she was firing her gun. And I just said, 'Shooter,' and everybody started running," Arnspiger said.
President Donald Trump tweeted, "Our thoughts and prayers are with everybody involved. Thank you to our phenomenal Law Enforcement Officers and First Responders that are currently on the scene."
Was just briefed on the shooting at YouTube’s HQ in San Bruno, California. Our thoughts and prayers are with everybody involved. Thank you to our phenomenal Law Enforcement Officers and First Responders that are currently on the scene.— Donald J. Trump (@realDonaldTrump) April 3, 2018
The FBI released a statement: "It is too early to make any clear assesment. We are currently following the evidence to determine if a federal violation has occurred."
(The Associated Press contributed to this report.)
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