YouTube HQ shooting: Here's everything we know

A suspected female shooter was found dead Tuesday inside YouTube's San Bruno, California, headquarters after apparently shooting three people at the video site's offices in the quiet Silicon Valley town.

YouTube employees began posting to Twitter about the shooting around 1 p.m. PT and described a chaotic scene.

The San Bruno Police Department identified the shooter as Nasim Najafi Aghdam, who eventually turned the gun on herself. Three others -- a 32-year-old woman, a 27-year-old woman and a 36-year-old man -- were transported to Zuckerberg San Francisco General Hospital with gunshot wounds.

The event rattled the tech industry, which has so far lived in relative comfort along the peninsula that's home to some of the world's largest companies, including Apple, Facebook, Hewlett-Packard and YouTube's parent company, Google (and its own parent company, Alphabet).

YouTube itself is the internet's biggest video site, a fact that drew more attention to the shooting. Silicon Valley CEOs and workers, as well as President Donald Trump, all tweeted about the situation as police descended on the community, putting up crime scene tape, shutting down intersections and stopping traffic on a nearby freeway for a short time.

Here's everything we know about the shooting so far.

Watch this: Here's everything we know so far about the YouTube shooter

01:24

Who was the shooter?

Police said the shooter was Nasim Aghdam, a 39-year-old woman from San Diego. 

The San Bruno Police Department is investigating the motive for the shootings. "At this time," read a statement Tuesday, "there is no evidence that the shooter knew the victims of this shooting or that individuals were specifically targeted."

However, there is evidence that Aghdam was angry at YouTube over the handling of her channels. Aghdam's family told CBS Los Angeles that she had become increasingly upset with YouTube when the site stopped paying for the content she posted online. Prior to the shooting, Aghdam's father said she had been missing for a few days. 

In a separate interview, Aghdam's brother told Fox 5 Las Vegas that he'd warned police that his sister had driven from San Diego to the Bay Area, and that he was worried she might do something.

Watch this: YouTube HQ shooter identified

01:03

What's her relationship with YouTube?

San Bruno Police Chief Ed Barberini confirmed that Aghdam was upset by the video streaming giant's policies and practices. 

Aghdam reportedly had a number of YouTube accounts and a website where she allegedly voiced concerns about YouTube and its monetization policies. 

Earlier reports indicated she may have known one of her victims and initially asked for the male victim by name, but she reportedly had no relationships with anyone at YouTube HQ.

Aghdam used the name "Nasime Sabz" online, according to CBS News. A website in that name decried YouTube's policies and said the company was trying to "suppress" content creators.

She had more than 10,000 subscribers on her YouTube channels, all of which have now been taken down.

Aghdam's family told CBS Los Angeles that she had become increasingly upset with YouTube when the site stopped paying for the content she posted online. Prior to the shooting, Aghdam's father said she had been missing for two days. 

Why was she angry about YouTube's policies?

For the last year and a half, YouTube has been buffeted by a backlash from both its advertisers and the creators who upload -- and sometimes earn their livelihoods from -- videos on the service. 

Last year, an outcry about commercials running next to offensive videos sparked an advertiser boycott. When YouTube responded by more aggressively pulling ads from sensitive clips, it ended up outraging people who uploaded videos that seemed fine but lost moneymaking power -- a development they dubbed "Adpocalypse." 

Didn't I hear this was a false-flag operation? And wasn't one of the Parkland shooting survivors there?

This is where the story takes a turn. As with other tragedies, including the recent shooting at Marjory Stoneman Douglas High School in Parkland, Florida, trolls and propagandists used the shooting to spread false stories about those involved. Others mocked the situation.

Unsurprisingly, Twitter became home to many of these conspiracy theories and hoaxes, an issue the company's CEO, Jack Dorsey, addressed in a tweet, promising action.

The trolling got so bad that someone hacked into the Twitter account of one of the YouTube survivors and posted tweets making fun of his name, among other things.

There was also an online threat of another shooting just hours after the incident, San Bruno police said on April 18. The threat, which was posted on Instagram, was traced to a "juvenile" in Pennsylvania. It was later determined to benign. Authorities haven't decided whether to file charges in the case.

What was the reaction?

The tech industry quickly rallied in a show of a support, tweeting out sympathy to the people affected by the YouTube shooting. Among others, Apple CEO Tim Cook, Amazon CEO Jeff Bezos and Twitter CEO Jack Dorsey all shared their dismay over the tragic event.

Google CEO Sundar Pichai, meanwhile, posted his thanks to first responders and a copy of a letter he sent to the team.

YouTube's CEO, Susan Wojcicki, tweeted her support for the victims.

The company released more details about the events, noting the shooter never entered the building. YouTube also said it's encouraging its employees to take some time off or work from home as they try to move forward from the shooting. 

I thought Google was based in Mountain View. Where's San Bruno?

Silicon Valley companies are known for their colorful sprawling campuses that stand as landmarks throughout the area. But the truth is that many of these companies' employees work in satellite offices in less glamorous locations throughout the Bay Area.

YouTube continues to operate out of San Bruno, where it was based after it was founded in 2005. It continued to operate there even after it was purchased by Google in 2006 for $1.65 billion. In fact, two years ago it bought multiple buildings to expand its presence to be able to house nearly 3,000 employees.

Originally published April 3 at 6:41 p.m. PT.

Update, April 5 at p.m. with information about an online threat of another shooting. 8:38 p.m. PT: Added identification of alleged shooter; 11:06 p.m. PT: Added police confirmation of the shooter; April 4 at 5:15 a.m. PT: To include additional details on the shooter; 5:15 a.m. PT: To include additional details on the shooter; 9:03 a.m. PT to add additional details about the shooter and clarify Google is based in Mountain View; 10:55 a.m. PT to add details from the San Bruno police chief and context about the YouTube policies; 4:32 p.m. PT: to add statement from Google.

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