A 20-year-old man from Pennsylvania fired multiple shots at former President Donald Trump at a rally on Saturday evening.

A bullet grazed the presumptive Republican presidential nominee’s upper right ear, leaving him bloodied but not seriously injured. One rally attendee was killed in the gunfire and two others were “critically injured,” authorities later said.

Here’s what we know:

Who is the shooter at the rally?

The FBI identified Thomas Matthew Crooks of Bethel Park, Pennsylvania, as the person behind the assassination attempt. Agency officials released little additional information, saying its investigation remains active and ongoing. They did not indicate what Crooks’ motive might have been.

Crooks worked at a nearby nursing home. An administrator there told USA TODAY that the company was shocked to learn of the shooting and that Crooks had passed a background check for his job.

What did Thomas Crooks do at the crime scene?

During the shooting Saturday, Trump’s right ear was injured, seconds before he was whisked off stage by Secret Service personnel. One man attending the rally was killed and two others were injured; Crooks was then killed by Secret Service agents, authorities said.

FBI special agent Kevin Rojek said on a call with media Sunday afternoon that authorities found “a suspicious device” when they searched the shooter’s vehicle. Bomb technicians inspected the device and rendered it safe.

“I’m not in a position to provide any expertise on the specific components of any potential bombs or suspicious packages,” Rojek added.

Rojek said law enforcement is sending the rifle and Crooks’ cell phone, along with other evidence, to the FBI lab in Quantico, Virginia “for processing and exploitation.”

“We’re in the process of searching his phone,” Rojek said.

What is Crooks’ background?

Crooks is registered to vote as a Republican in Allegheny County, Pennsylvania, according to county voter records. His voter registration status has been active since 2021.

Federal Election Commission records show that in January 2021, Crooks made a $15 donation to the Progressive Turnout Project, a group working to increase voter turnout for Democrats.

Born Sept. 20, 2003, Crooks does not have a criminal record in Pennsylvania, nor has he been sued there, according to state court records. There is no record of him in federal court databases, either.

Where did Thomas Crooks work?

Crooks worked as a dietary aid, a job that generally involves food preparation, at Bethel Park Skilled Nursing and Rehabilitation, less than a mile from his home. In a statement provided to USA TODAY on Sunday, Marcie Grimm, the facility’s administrator, said she was “shocked and saddened to learn of his involvement.”

“Thomas Matthew Crooks performed his job without concern and his background check was clean,” Grimm said. “We are fully cooperating with law enforcement officials at this time. Due to the ongoing investigation, we cannot comment further on any specifics. Our thoughts and prayers go out to Former President Trump and the victims impacted by this terrible tragedy. We condemn all acts of violence.”

The facility is owned by Kennett Square, Pennsylvania-based Genesis Healthcare. A job posting from the company for a dietary aid in the Pittsburgh area puts the pay at $16 an hour.

Thomas Crooks from Bethel Park, Pennsylvania

Crooks’ home address is listed in Bethel Park, a suburb in the Pittsburgh metropolitan area, voter records show. That three-bedroom brick house has been owned since 1998 by Matthew and Mary Crooks, who appear to be his parents. Telephone calls to the couple were not returned overnight.

Near the Crooks home, Dean Sierka, 52, said he had known Crooks and his parents for years, as neighbors separated by only a few houses. Sierka’s daughter, Lily Sierka, attended school with Crooks from elementary school through Bethel Park High School, and said she remembers him as quiet and shy.

Dean and his daughter Lily said they would see Crooks at least once a week, often when Crooks was walking to work.

“You wouldn’t have expected this,” Dean Sierka said. “The parents and the family are all really nice people.”

At Bethel Park High School

Jason Kohler attended Bethel Park High School with Crooks and said he remembers the 20-year-old sat alone at lunch and was “bullied every day.” Kids picked on Crooks for wearing camouflage to class and his quiet demeanor, Kohler, 21, said.

Since hearing Crooks has been named as the shooter, Kohler has been speaking with classmates who knew him, most of whom are stunned by the news.“It’s really hard to comprehend,” he said.

Sean Eckert said he went to school with Crooks from 5th through 12th grade. He said Crooks always went by “Tom.”

They shared classes together in elementary and middle school. Eckert said Crooks, though “fairly smart,” was quiet and rarely spoke up.

Eckert said Crooks did not seem to have many friends. He didn’t recall Crooks being playing any sports, being involved in any clubs or student groups or going to popular campus events. He often wore hunting clothes, so Eckert assumed he hunted.

No one in Eckert’s group text from high school seemed to know Crooks very well, he said. They were shocked that someone from their town had done this. They were even more surprised that it was Tom Crooks.

The gaming-oriented online site Discord said Sunday that it had found an account that appeared to be linked to the shooting suspect. The site removed the account, which “was rarely utilized, has not been used in months, and we have found no evidence that it was used to plan this incident, promote violence, or discuss his political views,” according to a statement from a Discord spokesperson, adding that the company will coordinate closely with law enforcement.

Where is Bethel Park, Pennsylvania?

Bethel Park is a suburb of Pittsburgh and home to more than 32,000 people – about one thousand fewer than four years ago, according to the latest Census estimates.

The majority-white, mostly college-educated community has a median household income of $102,177.

Described as a charming retreat from the hustle and bustle of the big city to its north, Bethel Park boasts tree-line streets, friendly neighborhoods and a low crime rate.

Bethel Park is about 42 miles south of Butler, where the Trump rally was held. The leafy suburban street was alive with law enforcement overnight amid a multi-agency response to the shooting. A member of the Allegheny County bomb squad told reporters his team was headed into the house around midnight, but did not say why.

For hours afterward, the scene remained quiet, with deer passing under the police tape and an occasional neighbor stepping out of their house to see what was happening.

John Wolf, a local construction superintendent who lives down the road, said he’d talked with several worried neighbors.

“People are scared,” Wolf said.

How did Crooks shoot at Trump?

Crooks had been positioned on a rooftop more than 100 yards from the rally site, Secret Service spokesperson Anthony Guglielmi said. Law enforcement recovered an AR-style rifle from the scene.

Joseph Price, special agent in charge of the ATF in Pittsburgh, said the weapon used by the shooter was a rifle.“It was nothing special,” he said in an interview in the parking lot of the Butler Township Municipal Building.

Law enforcement is following up on a “number of suspicious occurrences,” said Lt. Col. George Bivens of the Pennsylvania State Police, including accounts from witnesses who said they tried to flag police about the activity of a person outside the rally moments before the shooting.

The FBI said in a news release that the situation “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.”