After Crooks fired multiple shots from an AR-style rifle, a Secret Service sniper shot and killed him.

In a briefing Sunday, the FBI said that limited insights from his recent communications didn't reveal anything about Crooks' motive, or suggest that anyone else was involved.

But some answers may lie in Crooks' cell phone, which the FBI shipped to its lab in Virginia.

Crooks lived in Bethel Park, Pennsylvania, about an hour's drive south of Butler, where the rally took place.

He graduated from Bethel Park High School in 2022.

He seemed to have little social media presence, or record of political activism.

He was quiet, but like he was just bullied, like he was bullied so much.

He'd wear hunting outfits sometimes.

Pennsylvania voting records show that he was a registered Republican.

And on the day of Joe Biden's inauguration, a Federal Election Commission record shows Crooks gave $15 to the Democratic-aligned Progressive Turnout Project.

Crooks did appear to have an account on Discord, a messaging app.

A Discord spokesman said he hadn't posted on that account in months, and that the platform had removed his account based on its off-platform behavior policy.

Witness accounts placed Crooks on a roof less than 450 feet away from Trump.

We noticed a guy crawling, bear crawling up the roof of the building beside us, 50 feet away from us.

Crooks' father, who the gun had belonged to, assumed his son had gone to a gun range, but became concerned when he couldn't reach him, according to people familiar with the investigation.

He called police after news of the shooting.

The FBI also said that Crooks hadn't been on the agency's radar as a possible threat before the shooting, and that there were no signs of mental health issues.