Transcript for Officials Investigating Anti-US Facebook Rant Believed Linked to OSU Attacker
We have learned of a Facebook post, just moments before this all happened. ABC's chief investigative correspondent Brian Ross with the new clues at this hour, into what might have motivated the suspect to do this. Reporter: Just three minutes before the first 911 call today, Abdul razak Ali artan posted this message on Facebook, according to law enforcement officials. "I can't take it anymore. America. Stop interfering with other countries, especially the Muslim ummah. We are not weak. We are not weak. Remember that." Authorities need to treat this as a potential terrorist attack. Reporter: As police and the FBI tonight carry out a search warrant at artan's home in Columbus -- Talk to anybody who he might have associated with, find out what they knew. Reporter: -- The picture emerging of him is that of a somali immigrant who, in this school video, taken just five months ago, seemed to be living the American dream. Until he turned on his adopted country, becoming radicalized based on what he read and heard online. Artan was recently profiled in the campus newspaper "The lantern," blaming the media for making muslims feel scared. So many people who have flipped by ISIS propaganda remotely look like they're leading successful lives. It's so hard to predict when the propaganda will get through to them to the point where they crack and go violent. Reporter: In recent weeks, ISIS has been urging its followers to copy the vehicle attack that took place in nice, France, when 84 people were killed by a terrorist driving a semitruck through the ba teal day celebration there. And just two days ago, ISIS posted this new video, instructing its followers how to use a knife to attack nonbelievers. Back to the suspect, and it would appear, such a stark contrast, a few months ago at that graduation he was at. Reporter: So happy. New other clues from the Facebook post? Reporter: He actually calls himself in that Facebook post a lone wolf. And he says, if you want muslims to stop carrying out lone wolf attacks, then make peace with the Muslim words. His words today. All right, Brian Ross, you'll stay on this throughout the night. Thank you.
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