Federal law enforcement agents are working on a roadmap to a motive, digging into paperwork and electronics found in the family home where the shooter lived.
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Early on they found a list of possible targets, including Michigan State, and now have his Facebook account and other social media sites frequented by the 43-year-old killer.
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After scouring the shooter's home and social media sites, MSU, U.S. and state investigators now know the campus attacker displayed warning signs from an apparent pre-occupation with exorcism to a run-in with police that should have precluded him from owning firearms.
The I-Team talked with former Homeland Security intelligence undersecretary John Cohen, who is now a contributor at ABC News.
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I-Team Insider: Search for answers after MSU shooting
"We've already learned that this was a troubled individual who felt socially isolated, socially disconnected -- he was angry about his personal life. He exhibited an online activity that indicated an interest in extreme religious and possibly other ideological beliefs," Cohen said.
Before being branded as dangerous and taken down, a Facebook page that authorities have linked to the Michigan State mass killer featured pictures from the Exorcist movie and exorcism practitioners. It was topped by a Bible Gospel that refers to snakes and scorpions and overcoming the power of the enemy. "Nothing will harm you," the passage reads.
Monday night after the shooter brought harm to eight MSU students, killing three of them, a non-partisan think-tank focused on extremism and analyzed the gunman's digital footprint, saying it suggests he "may have been influenced by a perceived 'war' with demons" by consuming discussions of 'spiritual warfare' and a plague of demons."
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"Could the authorities have monitored more closely and stop this before it happened? Theoretically, yes, but the social media is a vast world. It's very hard to monitor all of it," said ABC7's legal analyst and former Chicago federal prosecutor, Gil Soffer,
"We've learned is very often they do exhibit behaviors prior to the attack that are a cause for concern and may indicate their intent to engage in violence. So it's not like they're not on the radar screen. We're just looking at the wrong radar screen," Cohen said.
As work on the roadmap to a motive grinds on in Michigan, so too does an often-heard discussion about how to stop the next mass shooting --with those familiar red flags only now becoming evident: a perceived mentally unstable man, absorbed by aberrant social media personalities and with access to guns he wasn't legally entitled to have.
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