LOS ANGELES (KABC) -- The terrorist attack in New Zealand was designed to reach an audience on social media. An 87-page manifesto was posted online spreading anti-Muslim hate before the terrorist entered two mosques, and the manifesto directed viewers to a Facebook livestream.
"This person is trying to market his crime and trying to inspire others. Social media is all about messaging to others and the world," said Steve Gomez, Eyewitness News terrorism and security expert.
The livestream lasted 17 minutes.
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In a statement, Mia Garlick with Facebook New Zealand wrote, "Police alerted us to a video on Facebook shortly after the livestream commenced, and we quickly removed both the shooter's Facebook and Instagram accounts and the video. We're also removing any praise or support for the crime and the shooter or shooters as soon as we're aware."
But hours after the attack, the video was still appearing on some Facebook pages and sites, including Twitter, YouTube and Reddit.
"I don't think that social media companies are doing nearly enough to prevent this kind of content, this kind of violence to be depicted on their platforms," Gomez said.
Terrorism experts say the existence of a terrorist attack livestream with a large audience is used for recruiting and encourages copycats. Dr. Clifford Neuman, the director of USC's center for computer systems security, explained why social media companies struggle to control content on their sites.
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"Once the message is out there, much of the message end up getting either re-tweeted or re-posted by others, not necessarily with terrorist intent, but because this is very sensational," said Neuman.
Neuman also said a 17-minute video cut down into pieces can be difficult for platforms to detect.
"It is sometimes more difficult for them to immediately identify it as identical, and it need to go through another cycle before it gets taken down," Neuman added.
Facebook says they continue to work with New Zealand police as their response and investigation continues.
New Zealand terror attack designed to reach audience on social media