The 20-year-old man who tried to assassinate former President Donald Trump first came to law enforcement’s attention at Saturday’s rally when spectators noticed him acting strangely outside the campaign event. The tip sparked a frantic search but officers were unable to find him before he managed to get on a roof, where he opened fire.

In the wake of the shooting that killed one spectator, investigators were hunting for any clues about what may have drove Thomas Matthew Crooks, of Bethel Park, Pennsylvania, to carry out the shocking attack. The FBI said they were investigating it as a potential act of domestic terrorism, but the absence of a clear ideological motive by the man shot dead by the Secret Service led conspiracy theories to flourish.

“I urge everyone — everyone, please, don’t make assumptions about his motives or his affiliations,” President Joe Biden said in remarks Sunday from the White House. “Let the FBI do their job, and their partner agencies do their job. I’ve instructed that this investigation be thorough and swift.”

The FBI said it believes Crooks, who had bomb-making materials in the car he drove to the rally, acted alone. Investigators have found no threatening comments on social media accounts or ideological positions that could help explain what led him to target Trump before the Secret Service rushed the presumptive Republican presidential nominee off the stage, his face smeared with blood.... Read More: Associated Press