EMBED >More News Videos PHOTOS: Shooting at YouTube headquarters in San Bruno (1 of 7) Police and witnesses say a woman opened fire Tuesday at YouTube headquarters in San Bruno, wounding three people before fatally shooting herself as terrified employees huddled inside.

SAN BRUNO, California -- Sources confirm to sister station KGO in San Francisco that the YouTube shooter was a user of the platform, and that Nasim Aghdam had a website with a manifesto that targets YouTube for censorship and demonetization of her video content.Aghdam is said to have no relationship with anyone in the YouTube facility, where authorities say she pulled out a handgun and fired several rounds in a courtyard at the company's headquarters in San Bruno Tuesday. She wounded three people before killing herself, police said.Sources say Aghdam did not have an ID badge but was carrying a purse, and nobody in the facility knew who she was.According to her website, a possible motivation for the shooting could have been tied to her many YouTube accounts, which she said have seen a decline in viewership over the past few months.She embedded videos from the biggest YouTubers on the platform on the site, including massive creator Casey Neistat. In them, they talk about the YouTube "Ad-apocalypse," where many users are seeing massive dips in traffic, subscriber count loss, and demonetization of videos.Neistat has more than 9 million subscribers and made a famous video about the YouTube ad revenue scare for creators.It appears Aghdam was disgruntled by the changes in the YouTube platform."Be aware! Dictatorship exists in all countries but with different tactics!" she wrote on her website. "They only care for personal and short-term profits and do anything to reach their goals even by fooling simple-minded people, hiding the truth, manipulating science and everything, putting public mental and physical health at risk, abusing non-human animals, polluting the environment, destroying family values, promoting materialism and sexual degeneration in the name of freedom and turning people into programmed robots!"She goes on to quote Adolf Hitler saying, "Make the lie big, make it simple, keep saying it and eventually they will believe it."The rest of her message targets YouTube and censorship."There is no free speech in the real world and you will be suppressed for telling the truth that is not supported by the system," she wrote. "Videos of targeted users are filtered and merely relegated so that people can hardly see their videos."On February 20, YouTube enacted a new advertising policy that demonetized channels with less than 1,000 subscribers and 4,000 hours of watch time. Though Aghdam's main English channel had more than 5,000 subscribers, many of her videos appeared to be demonetized.One of the victims, a 36-year-old man, was in critical condition, a spokesman for San Francisco General Hospital said. A 32-year-old woman was in serious condition and a 27-year-old woman in fair condition, the spokesman said.----------