YouTube shooter's brother said he warned police in advance

The brother of Nasim Najafi Aghdam worried she might do something dangerous.

The concerns started over the weekend when Aghdam stopped answering her phone, her brother told CNN affiliate KGTV. Then the San Diego resident's car was found more than 700 miles northwest, in Mountain View, California.

"I Googled 'Mountain View,' and it was close to YouTube headquarters. And she had a problem with YouTube," said Aghdam's brother, who did not want to be identified.

So he called police to say "she went all the way from San Diego, so she might do something."

That fear turned into reality Tuesday afternoon when Aghdam shot three people at the YouTube campus in San Bruno before killing herself with a handgun.

But it's unclear whether the brother's concerns were relayed to authorities in the Bay Area, San Bruno police Chief Ed Barberini told ABC's "Good Morning America" on Wednesday.

"We know that she was reported missing by her family in San Diego on the 31st of March, and that she was located in a community about 30 miles south of us early Tuesday morning," Barberini said.

"I don't know what concerns were conveyed to that police department, or how or where those concerns were relayed to. So that is something we're looking into."

Authorities gave conflicting accounts of whether Aghdam knew any of her three victims, who are hospitalized in fair, serious and critical condition.

Shortly after the shooting, two law enforcement officials told CNN the shooter knew at least one victim. But on Tuesday night, police said they have no evidence Aghdam knew any of the victims or whether they were targeted.

Barberini said the motive remains uncertain. But police are investigating a website that appears to show the same woman accusing YouTube of restricting her videos, according to the Los Angeles Times.

CNN is working to confirm the authenticity of the website, which lists four YouTube channels: one in Farsi, one in Turkish, one in English and one devoted to hand art. It also lists an Instagram page that focuses on vegan life.

The woman's grievances against YouTube appear to focus on censorship and revenue.

"There is no equal growth opportunity on YOUTUBE or any other video sharing site, your channel will grow if they want to!!!!!" one post reads. "Youtube filtered my channels to keep them from getting views!"

Another post accuses "close-minded" YouTube employees of putting an age restriction on videos, saying it's aimed at reducing views and discouraging the woman from making new videos.

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