How a young man with no clear motive tried to kill former President Donald Trump

The FBI is still searching for a motive behind the attempted assassination of former President Donald Trump during his rally in Pennsylvania on Saturday.

The agency identified the shooter as 20-year-old Thomas Matthew Crooks from Bethel Park, Pennsylvania, a Pittsburgh suburb about an hour's drive from the shooting at the rally venue in Butler. Officials believe he acted alone, and they are investigating the shooting as a case of domestic terrorism.

Crooks' name has links to both the Democratic and Republican parties.

Records obtained by Scripps News from the Federal Elections Commission show a donation to Democrats by someone named Thomas Crooks, with the same address as the shooter.

In January 2021, Crooks gave $15 to the Progressive Turnout Project, which is described on its website as “the largest voter contact organization in the country, specifically dedicated to mobilizing the Democratic Party and defending democracy.”

But then eight months later, Crooks identified himself as a Republican when he registered to vote at age 18.

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Crooks has no criminal past and no history of mental health issues, according to law enforcement.

Crooks worked as a dietary aide at Bethel Park Skilled Nursing. The administrator of the nursing home said he had a clean background check when he was hired.

He graduated from Bethel Park High School in June 2022. A man named Jason Kohler claimed he went to school with Crooks and described him as a typical outcast who was often alone.

The Associated Press reports that at the time of the shooting, Crooks appeared to be wearing a T-shirt from "Demolition Ranch." It’s a popular YouTube page that has demonstrations of guns and explosives.

The host of "Demolition Ranch" posted to his Instagram page a picture of what appears to be the downed shooter, with the words, "What the hell” following the shooting at the Trump rally. Scripps News reached out to him and we have not heard back.

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Investigators are working to determine how the shooter was able to get to a position at the rally venue from which he could fire shots at Trump. The shooting left one man dead and injured the former president and two rally attendees.

The Associated Press, citing an unnamed law enforcement source, said rally attendees had warned officers about a man acting suspiciously and that the gunman used a ladder to gain access to the rooftop where he fired multiple rounds toward Trump.

In an interview with CNN, Butler County Sheriff Michael Slupe said one of his officers encountered the shooter before he fired the gun, but he was unable to stop him.

Crooks was ultimately taken down by Secret Service agents shortly after he began firing. An AR-style rifle was found near the shooter at the scene and officials said they believe the gun belonged to the shooter's father, but they are still investigating how he obtained it.

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After the shooting, the FBI said it searched Crooks' residence and vehicle for evidence and found suspicious devices in both places. The devices, along with the shooter's phone, are now being evaluated at an FBI laboratory.

Crooks' family is cooperating with authorities.