A female shooter stormed YouTube's headquarters in San Bruno, California, injuring four people before turning the gun on herself.
The "white adult female" was found dead from a self-inflicted gunshot by police inside the building. Four other people were injured, including a man, 37, who was taken to hospital with critical injuries.
Two women were also injured in the shooting. One is listed as "serious" and the other is "fair". Another person is believed to have non-life threatening injuries. Two victims were found at a nearby business, said San Bruno police chief Ed Barberini.
A worker at a Carl's Jr restaurant next to the YouTube campus said one woman was shot in the carpark and brought into the restaurant to be cleaned up.
Witnesses told Fox News the woman shot her boyfriend and then herself, but police have yet to confirm that.
A spokesperson for Zuckerberg San Francisco General Hospital said at least five patients have arrived from the shooting and more are expected. Stanford Hospital said up to five patients were on the way to hospital. Their conditions and injuries are unknown.
Workplace shootings
• Feb 1, 2018: Former trucking company employee, Vernest Griffin, faced first-degree murder charges after two fatal shootings at separate Detroit-area businesses. Griffin was wounded and arrested after a shootout with police.
• June 14, 2017: UPS employee Jimmy Lam, who had recently filed a grievance, opened fire inside one of the company's San Francisco packing facilities, killing three co-workers before fatally shooting himself as employees fled frantically into the streets.
• June 5, 2017: John Robert Neumann jnr fatally shot five former colleagues and then himself at a manufacturer of awnings in Orlando, Florida. Neumann had been fired from the Fiamma factory in April.
• Oct. 25, 2016: One worker was fatally shot and three others were wounded after a former co-worker opened fire in the paint shop at FreightCar America in Roanoke, Virginia. The shooter, Getachew Fekede, then killed himself.
• Feb 2016: Fifteen people at Excel Industries, Kansas, were shot and three killed by a co-worker who police said had also shot two other people as he drove to the facility.
• Dec 2, 2015: A husband and wife shot his co-workers with high-powered rifles at a health department training event and holiday party at the Inland Regional Centre in San Bernardino, California. Syed Rizwan Farook and his wife Tashfeen Malik killed 14 people and wounded 22 others. They fled the scene but died in a shootout with police.
Staff told media outside the building that a female employee was shot in the left leg. Another staff member used a bungee cord as a tourniquet to slow the bleeding.
"She had a leg injury, a gunshot wound, so I put a tourniquet on her to try to help her" - a witness describes helping an injured female at YouTube HQ where police are hunting an 'active shooter' pic.twitter.com/l2Bd4gAvQZ
— Sky News (@SkyNews) April 3, 2018
BREAKING: YouTube shooter is a female and she is down, multiple law enforcement sources tell @NBCNews - @anblanxhttps://t.co/YQ0x5rJFwo
— NBC News (@NBCNews) April 3, 2018
Vadim Lavrusik, who works on YouTube's product team, tweeted that he heard shots and saw people running.
"Now barricaded inside a room with co-workers," he wrote. He later tweeted that he had safely left the building.
Todd Sherman, a product manager at the company, described the frightful moments evacuating the building.
"I looked down and saw blood drips on the floor and stairs," he wrote on Twitter.
"Peaked [sic] around for threats and then we headed downstairs and out the front."
Videos shared on social media appeared to show workers leaving the building, their hands above their heads, and police rushing in.
Staff evacuate the building. Photo / Twitter
Google, which owns YouTube, said it was cooperating with authorities.
"We are coordinating with authorities and will provide official information here from Google and YouTube as it becomes available," the company said.
The White House says President Donald Trump has been briefed on the YouTube shooting.
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