The 20-year-old who attempted to assassinate former President Trump at a July 13 rally in Butler, Pennsylvania, "carefully planned" and scoped out the Butler, Pennsylvania, rally-sight, the FBI revealed on Monday.
"We believe the subject made significant efforts to conceal his activities," FBI officials said during a conference call.
The FBI said that Crooks engaged in "careful planning ahead of the campaign rally" prior to the fateful Trump rally that left one dead and three injured, including the former president.