The FBI believes Thomas Matthew Crooks, 20, of Bethel Park, Pennsylvania, acted alone in what is being investigated as an assassination attempt on former President Donald Trump and a possible act of domestic terrorism.
In an update Sunday afternoon, officials with the agency said the investigation is far from over, noting that agents are trying to learn about the shooter's movements in the days and weeks before the Trump rally.
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Officials are still trying to determine a motive and the shooter's ideology, but they hope his phone, which was sent to an FBI lab in Virginia, will provide them with answers. They are also combing over the suspect's social media accounts, officials said.
"The American people can rest assured that we will leave no stone unturned as we work to get to the bottom of what happened," said FBI Director Christopher Wray.
Law enforcement confirmed Sunday they found bomb-making materials in the suspect's vehicle and home, located in a suburb outside of Pittsburgh about an hour away from where the rally took place. The vehicle was seized and also sent to the FBI lab in Virginia.
An AR-style rifle was found near the shooter at the scene of Saturday's rally in Butler, Pennsylvania. Officials said they believe the gun belonged to the shooter's father, but they are still investigating how he obtained it.
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 features demonstrations of guns and explosives.
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A Bethel Park man who claims to have gone to Bethel Park High School with the shooting suspect before graduating in 2022 described him to Scripps News as an "outcast" who was bullied in school.
Bethel Park School District can confirm that the alleged shooter in the July 13, 2024, assassination attempt on former President Donald J. Trump is a graduate of Bethel Park High School. Thomas Matthew Crooks graduated from Bethel Park High School with the Class of 2022.
In a statement, the Bethel Park School district said it will "cooperate fully with the active law enforcement investigation surrounding this case."
The shooter had no criminal history or known mental health issues, officials said. His family is reportedly cooperating with authorities.
The FBI is leading the investigation into the shooting and said anyone with information that may assist with the investigation is encouraged to submit photos or videos online at fbi.gov/butler or call 1-800-CALL-FBI.