2017 attacker made online threats; FBI met him in 2016 over assault rifle comments
Sometime in 2012, other users of an online forum were concerned after the student made threats about attacking his school. In March 2016, federal investigators met with the student after he made comments in an online chat room about wanting to find an inexpensive assault rifle he could use for a mass shooting. At the time, a family member told the investigators that the student was troubled and liked to make outlandish statements.
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Step 5: Establish Assessment Procedures