Washington — 

The 20-year-old gunman who tried to assassinate former President Donald Trump in July was dead set on carrying out an attack but appears to have seen the former U.S. leader and current Republican presidential candidate as a “target of opportunity.”

Senior FBI officials shared the updated assessment of Thomas Matthew Crooks on Wednesday, saying the findings are based on almost 1,000 interviews and extensive analysis of his internet search activity and social media accounts.

“We saw through our analysis of all his — particularly his online searches — a sustained, detailed effort to plan an attack on some event,” FBI Special Agent-in-Charge Kevin Rojek told reporters during a phone briefing.

“He looked at any number of events or targets,” Rojek said, adding that when the Trump campaign announced the July 13 rally in Butler, Pennsylvania, the shooter “became hyperfocused on that specific event.”

As for what motivated Crooks to carry out an attack in the first place, officials said that remains a mystery.

“At this time, the FBI has not identified a motive,” said Robert Wells, executive assistant director of the FBI’s National Security Branch.

Wells also said the FBI investigation has found no credible evidence to suggest that the shooter told anyone of his plans or that he had any help from any individuals or foreign governments.

“I want to be clear. We have not seen any indication to suggest Crooks was directed by a foreign entity to conduct the attack,” he said.

The FBI officials further rejected conspiracy theories that have been circulating on social media regarding a potential second shooter.

They said a forensic examination of the shooter’s gun, an AR-style rifle, conclusively linked the weapon to all eight shell casings found on the roof of the building where he carried out the attack.

The FBI officials said only two other shots were fired — one by a local law enforcement officer, and one by a U.S. Secret Service sniper — which hit the shooter in the head, killing him.

FBI investigators have been scouring Crooks’ internet searches and social media activity, and talking to anyone who knew him, ever since he climbed on a roof of a building overlooking the Trump campaign rally in rural, western Pennsylvania and began shooting, leaving Trump with a bloody ear and killing a rallygoer and injuring two others.

Last month, FBI Director Christopher Wray told lawmakers that Crooks appeared to have become fixated on high-profile public figures and that just a week before the attempted assassination, he searched for information on the 1963 killing of U.S. President John F. Kennedy by Lee Harvey Oswald.

“On July 6, he did a Google search for, quote, ‘How far away was Oswald from Kennedy?'” Wray said.

“That’s obviously significant in terms of his state of mind,” Wray added. “That is the same day that he registered for the Butler rally.”

FBI officials on Wednesday presented a more-detailed account of Crooks’ mindset and planning, saying the shooter appears to have started preparing to carry out an attack or shooting as far back as September 2023, using an online account to look at Trump’s campaign schedule.

Starting in April of this year, officials said, the shooter began researching campaign events for Trump and U.S. President Joe Biden.

“In the 30 days prior to the attack, the subject conducted more than 60 searches related to President Biden and former President Trump,” said the FBI’s Rojek, adding the shooter also looked up the dates and locations of the Republican and Democratic national conventions.

But Rojek said that Crooks’ focus on carrying out an attack appears to go back even further, and that he began researching how to make explosives in September 2019.

He said there is also no indication, so far, that Crooks was motivated by any political leanings.

“We've seen no definitive ideology associated with our subject either left leaning or right leaning,” Rojek said. “It's really been a mixture, and something that we're still attempting to analyze and draw conclusions on.”

It also appears Crooks was clear-headed and methodical in his attempt to kill Trump. Lab tests showed no signs he was using alcohol or illicit drugs at the time of the attack, FBI officials said.