The FBI early Sunday said a 20-year-old man from Bethel Park, Pennsylvania was the shooter in an assassination attempt on President Trump Saturday evening.

Thomas Matthew Crooks was registered in the state as a Republican voter but donated $15 to a progressive political action committee on January 20, 2021, the day President Biden was sworn in to office.

Secret Service officials said the investigation remains active and ongoing and have asked the public for assistance. Trump was reportedly in good spirits early Sunday on arrival at his golf club in Bedminster, New Jersey.

Secret Service agents fatally shot Crooks, who attacked from an elevated position outside the rally venue at a farm show in Butler, Pennsylvania, the agency said. One attendee was killed and two spectators were critically injured, authorities said. All were identified as men.

According to press reports, the gunman had no criminal history evident in the state’s public court records. Early Sunday morning, police had closed down all roads leading to the suspect’s home south of Pittsburgh, about an hour’s drive from the site of the Trump rally in Butler, Pennsylvania.

Reached by CNN late Saturday night, Crooks’ father, Matthew Crooks, said he was trying to figure out “what the hell is going on” but would “wait until I talk to law enforcement” before speaking about his son.

Crooks didn’t have any identification on his body at the scene, so agents had to “run his DNA and get biometric confirmation,” according to the special agent in charge of the FBI’s Pittsburgh field office, Kevin Rojek. 

The younger Crooks graduated in 2022 from Bethel Park High School, which has about 1,400 students, and received a $500 “star award” that year from the National Math and Science Initiative, according to a report in The Tribune-Review in western Pennsylvania.

In an online recording of the 2022 graduation ceremony, Crooks can be seen crossing the stage after his name is called out, a slender young man with glasses in a black graduation gown who briefly posed with a school official and accepted his diploma.

In a social media post early Sunday morning, Trump pledged to carry on with this week’s Republican National Convention at Milwaukee and called on Americans of all stripes to “stand united” and not allow “evil to win.”

“Thank you to everyone for your thoughts and prayers yesterday, as it was God alone who prevented the unthinkable from happening,” Trump said. “We will FEAR NOT, but instead remain resilient in our Faith and Defiant in the face of Wickedness. Our love goes out to the other victims and their families. We pray for the recovery of those who were wounded, and hold in our hearts the memory of the citizen who was so horribly killed.”

“In this moment, it is more important than ever that we stand United, and show our True Character as Americans, remaining Strong and Determined, and not allowing Evil to Win,” Trump said. “I truly love our Country, and love you all, and look forward to speaking to our Great Nation this week from Wisconsin.”