What we know about the Trump rally shooter

The gunman who fired shots at former President Donald Trump in an assassination attempt at a campaign rally in Butler, Pennsylvania, Saturday night has been identified by the FBI as 20-year-old Thomas Matthew Crooks. He was killed by a Secret Service sniper, officials said.

One audience member at the rally, Pennsylvania firefighter Corey Comperatore , was killed in the shooting, and two other men are in critical condition, officials said.

Who was the shooter?

In a statement, the FBI said:

"The FBI has identified Thomas Matthew Crooks, 20, of Bethel Park, Pennsylvania, as the subject involved in the assassination attempt of former President Donald Trump on July 13, in Butler, Pennsylvania. This remains an active and ongoing investigation, and 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."

Federal investigators said the gunman was not carrying identification, so they analyzed his DNA to provide a biometric confirmation of his identity.

Crooks was from Bethel Park, Pennsylvania, a Pittsburgh suburb about an hour south of Butler. The town in Allegheny County is home to about 30,000 people and has one high school with about 1,300 students.

Bethel Park School District confirmed to CBS Pittsburgh station KDKA that Crooks was a 2022 graduate of Bethel Park High School. School officials pledged to work with law enforcement investigating the shooting, and offered condolences to those affected by the attack.

Former classmate Jameson Myers, a member of the school's varsity rifle team, told CBS News that Crooks had tried out for the team freshman year but did not make the junior varsity roster and did not return to try out for the team in subsequent years.

He called Crooks a "nice kid who never talked poorly of anyone and I never have thought him capable of anything I've seen him do in the last few days."

What was his motive?

"We do not currently have an identified motive," said Kevin Rojek, FBI Pittsburgh special agent in charge, at a briefing late Saturday night.

A law enforcement official said early Sunday that there are no foreign terrorism ties known at this time and the suspect was not on the radar of law enforcement, although they are still running his name down.

There was also no indication that Crooks ever had a connection to any military branch, officials confirmed to CBS News.

Crooks' political leanings were not immediately clear. Records show he was registered as a Republican voter in Pennsylvania but previously made a $15 donation to a Democratic-aligned group, KDKA reported .

A law enforcement official said early Sunday that the Secret Service and the FBI are investigating the suspect's background and speaking with his family. The FBI has secured his home and federal law enforcement is searching his family's residence in suburban Pittsburgh, the law enforcement official said.

What weapon did he have?

The gunman was armed with a semiautomatic AR-style rifle, multiple law enforcement sources said. ATF is tracing the weapon.

Two law enforcement sources told CBS News on Sunday the gun was legally purchased by and registered to the shooter's father, Matthew Crooks.

The gunman opened fire from the roof of a shed outside of the cordoned-off rally area, about 400 feet from the stage, multiple sources said.

A law enforcement source confirmed Sunday that suspicious devices were found in the gunman's vehicle. CBS News has learned the shooter had a device in his possession that appeared to be capable of triggering those suspicious devices. Bomb technicians called to the scene were involved in securing and investigating the devices.

What protections were there for Trump?

Trump said in a social media post that a bullet pierced the upper part of his right ear. He was checked at a local hospital before leaving the area under Secret Service protection and flying to New Jersey late Saturday night.

Trump's Secret Service detail was given additional assets that are part of the protocol for the presumptive nominee due to his heavy campaigning, which includes additional manpower, counter-sniper, drones and robotic dogs, the law enforcement official said. On Saturday, there were four counter-sniper teams on site, the official said.

Additionally, Trump's teleprompter is protective and the flag and podium banners are made of steel, the law enforcement official said.

In a statement Sunday morning, U.S. Secret Service spokesperson Anthony Guglielmi said the agency recently "added protective resources and capabilities to the former President's security detail," and said any suggestion that they had rebuffed a request for more security "is absolutely false."

"The U. S. Secret Service takes threats seriously, and it takes actions based on those threats as warranted," he said. "The U.S. Secret Service is constantly evaluating the very dynamic threat environment and responding to it in the fulfillment of its responsibilities."

The FBI is leading the investigation into the shooting. On Sunday, President Biden said he has ordered an independent review into what took place.

What did witnesses see?

One man who was at the rally said that soon after Trump started speaking, he saw a man "bear crawling" up a building.

"We're pointing at the guy," said the witness, named Greg. "He had a rifle — you could literally see him with a rifle." He told the BBC that he and others told the police and were pointing him out to U.S. Secret Service agents. He estimated that the man was on the roof for "three or four minutes" before shots were heard.

Other witnesses told CBS Pittsburgh station KDKA that they also saw the gunman and tried to alert officers before the shooting.