Richard D. Clayton, 26, was under a joint investigation by the FDLE, the Winter Park police department and the FBI’s Joint Terrorism Task Force that began on Aug. 6 after a Facebook post by Clayton said that he had "3 more days of probation left then I get my AR-15 back. Don’t go to Walmart next week.” The Walmart location was a possible reference to last week’s mass shooting that took place inside a Walmart in El Paso, TX.