A female suspect is confirmed dead and at least four victims wounded after multiple gunshots were fired inside YouTube headquarters in San Bruno, California Tuesday afternoon, police said.

The suspect is believed to have died of self-inflicted wounds, San Bruno Police Chief Ed Barberini told reporters. Barberini did not provide any details on the weapons the suspect used or on the motivation behind the shooting, but said the four victims have all been transported for emergency care. Three of those victims suffered gunshot wounds, police later confirmed.

“We anticipate being out here through the night as part of our investigative effort,” Barberini said at a second press conference Tuesday evening. Police spent the afternoon searching Youtube’s headquarters, which is located roughly 12 miles outside of San Francisco. FBI agents were also on the scene.

Police officers arrived at YouTube’s headquarters at 12:48 p.m. local time, minutes after receiving several 911 calls reporting gunfire, according to a press release issued by the San Bruno police department. Officers located one victim at the front of the building, and later located two more who had fled to a business next door.

The suspect used a handgun, Barberini told reporters.

Multiple senior law enforcement officials told NBC News that the shooting is believed to be related to a domestic incident rather than a terrorist attack, and that the suspect is in her thirties. VICE News has not yet independently confirmed the age of the suspect. The Los Angeles Times also reported that authorities do not believe the shooting to be an act of terrorism. The San Bruno Police Department hasn’t yet confirmed the motive of the shooting.

In a statement, Google — which owns Youtube — said it was cooperating with authorities and that Bay Area employees have been asked to stay away from the area.

Area hospitals confirmed receiving multiple patients from the scene. Stanford Health Care told the Huffington Post it is treating four to five patients from the incident, and a spokesperson for San Francisco General Hospital told the Associated Press that three patients, including a 36-year-old man in critical condition, had been admitted. A 32-year-old woman in serious condition and a 27-year-old woman in fair condition were also reportedly admitted.

A woman also showed up at the Kaiser Permanente medical center in south San Francisco with a twisted ankle from the incident, Joe Fragola, the center’s media relations manager, told VICE News.

About 1,700 people work in the office, according to ABC 7 San Francisco. Some of them described the scene on social media.

“Heard shots and saw people running while at my desk. Now barricaded inside a room with coworkers,” Vadim Lavrusik, a YouTube product manager, wrote on Twitter.

Todd Sherman, another product manager, described the chaotic scene: "We were sitting in a meeting and then we heard people running because it was rumbling the floor," he wrote on Twitter. "First thought was earthquake."

"After existing the room we still didn’t know what was going on but more people were running. Seemed serious and not like a drill. We headed towards the exit and then saw more people and someone said that there was a person with a gun. Shit."

"I looked down and saw blood drips on the floor and stairs. Peeked around for threats and then we headed downstairs and out the front. Police cruisers pull up, hopped out with rifles ready and I told them where the situation was as I headed down the street to meet up with a couple team members," Sherman, who said he was safely in an Uber home, tweeted.

Aerial shots of the scene appeared to show YouTube employees leaving the building in single file with their hands raised. Ibrahim Dababneh, the owner of Big Mouth Burgers — which is located across the street from Youtube headquarters — said that he saw a barrage of police officers and firefighters pull up outside the building.

Michelle Tam, a hostess at the Hashes & Brews restaurant located near the YouTube building, told the Los Angeles Times three YouTube employees came in after the shooting looking “visibly shaken.” One of the employees had a partial bullet fragment in her shoe, she said.

President Donald Trump tweeted his “thoughts and prayers” for people involved with the incident.

California Democratic Sens. Kamala Harris and Dianne Feinstein also tweeted about the incident, as did Democratic Rep. Jackie Speier. (The shooting took place in her district.) House Democratic Leader Nancy Pelosi also tweeted a call to end gun violence.

The shooting follows Youtube’s recent crackdown on videos that promote firearm sales and on tutorials about assembling firearms, which took place days after the Parkland, Florida massacre. March for Our Lives, the gun control group formed by survivors of the Parkland shooting also tweeted its solidarity with Youtube.

This is a developing story ...