Transcript for At least 4 injured in shooting at YouTube offices; suspect dead
And we begin with that breaking news from California. The active shooter emergency at YouTube headquarters in San Bruno. One of silicon valley's most high profile companies. Police cars responding to 911 calls from inside neighboring buildings. Outside, other buildings also put on lockdown. Multiple agencies responding to the scene. Heavily armed S.W.A.T. Teams going in, you see them there. Agents securing the scene, allowing people to come out, but with their hands in the air. About on the, we know the shooter was a woman, who is now dead, but four others are injured. ABC's senior national correspondent Matt Gutman with the details just coming in. Reporter: Shots fired during the lunch hour at the video colossus YouTube. The upturned chairs, the bullet casings and the police emergency calls. Active shooter at 901 cherry. Reporter: Now tragically familiar, but not this -- a female suspect. Confirming she is the suspect? Affirmative, what we were told. We did locate a victim with a -- what we believe to be a self-inflicted shot wound. It's a female. But the investigation is still ongoing. Reporter: This is believed to be the first female mass shooter since at least 2010. The call came in 12:46 local time. Two minutes later, police arrive, searching for the shooter. This is crazy. We're on lockdown. Upon arrival, officers encountered numerous employees fleeing from the building. It was very chaotic, as you can imagine. Reporter: Police moving forward, finding hundreds of employees fleeing, their hands raised. Teams proceeding to clear the building and searching each employee. Inside the Carl's Jr. In San Bruno. Medical aid. Reporter: This man tended to one of the wounded. Gunshot wound. So, I put a tourniquet on her to try to help her. The ambulance came and then they took her away, put a real tourniquet on her. Reporter: Hospitals and police reporting at least four victims have been hospitalized. And Matt Gutman joins us now. Matt, as you reported, police say they found four victims. What do we know about the victims' conditions right now? Reporter: Right now, we've spoken one of the major hospitals treating them, San Francisco general. They say they have received one male in critical condition. Another female in serious condition. And a third person, another female, in fair condition. And right now, police are just trying to figure out what happened here and figure out the actual nature of this attack. Tom? It's all still so fresh. All right, Matt, thank you so much. Much about the YouTube shooting following a common pattern. The shots ringing out, the lockdown, the massive police response, but what was different this time, the suspected shooter was a woman. ABC's chief justice correspondent Pierre Thomas on what we're learning about her tonight. Good evening, Pierre. Reporter: Tom, you're exactly right. It's still early, but they found the female suspect, a gun close by with that apparent self-inflicted gunshot wound. It's rare to hear women involved in this type of mass shooting. The secret service released a study that examined 20 mass attacks last year. All were carried out by males. They do happen, however. The San Bernardino attack, also in California, happened with a female and her husband. They are trying to identify this potential shooter, look into her background and try to find a motive. Did she target specific people, YouTube, an iconic company, or was this a terrorist attack? ATF will trace the gun, but it's still very early in this investigation, Tom. All right, Pierre, thank you. Next, we are also tracking end treatment weather at this
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