A female suspect died after a shooting that left multiple people injured at YouTube headquarters in San Bruno, Calif., Tuesday afternoon.
Police told the Associated Press they were investigating the incident as a domestic dispute.
They said the shooting took place in a courtyard in the YouTube complex and involved a handgun.
WATCH: Police, hospital officials provide details of YouTube HQ shooting
Three people were shot before the shooter apparently turned the gun on herself, San Bruno Police Chief Ed Barberini said at a press conference.
The three victims were transported to hospital. San Francisco General Hospital spokesperson Brent Andrew confirmed there was one male victim who is in critical condition. There were also two female victims — one in serious condition and the other in fair condition.
A fourth victim was taken to hospital with an injury sustained when fleeing the scene.
Police reported the active shooter at 12:46 p.m. PT at the location and warned civilians to stay out of the area. San Bruno is located about 20 kilometres south of San Francisco.
A police spokesperson said there were officers on scene within two minutes of receiving the call.
The FBI and ATF are both on scene to help with the investigation but say San Bruno police are leading it.
The shooting had no known connection to terrorism, a U.S. government security official told Reuters.
Alphabet Inc., parent company of YouTube and Google, released a statement on Twitter saying officials are coordinating with police.
“Re: YouTube situation, we are coordinating with authorities and will provide official information here from Google and YouTube as it becomes available,” the tweet reads.
“We are an incredibly tight knit community,” YouTube spokesperson Chris Dale said Tuesday afternoon. “Today it feels like the entire community of YouTube were victims of this crime.”
Dale said everyone’s thoughts were with the victims families, and thanked the police for their “rapid response. ”
Pictures and video from the scene show a SWAT team entering the building as employees filed out.
U.S. President Donald Trump was briefed on the situation and offered his “thoughts and prayers.”
San Bruno’s representative in Congress Jackie Speier said on Twitter she was following the developments and said there must be action to end gun violence.
On Twitter, employees of YouTube and and others working in nearby buildings said they were locked down.
“Heard shots and saw people running while at my desk. Now barricaded inside a room with coworkers,” YouTube employee Vadim Lavrusik wrote.
“We were sitting in a meeting and then we heard people running because it was rumbling the floor. First thought was earthquake,” YouTube product manager Todd Sherman said on Twitter.
Sherman described his experience in the building on Twitter. He said he was in a conference room when he heard people running and decided to evacuate.
“At that point every new person I saw was a potential shooter. Someone else said that the person shot out the back doors and then shot themselves,” Sherman said.
“I looked down and saw blood drips on the floor and stairs. Peaked around for threats and then we headed downstairs and out the front,” Sherman continued.
He said he was safe and on his way home.
*with a file from Reuters