Authorities have identified the gunman involved in the attack against former US President Donald Trump on Saturday as 20-year-old Thomas Matthew Crooks. Crooks, a resident of Bethel Park, Pennsylvania, was killed by Secret Service agents at the scene after opening fire on Trump during a rally in Butler.

According to law enforcement officials, Crooks fired on Trump from a rooftop outside the rally's security perimeter. The chaotic scene unfolded as witnesses described a "bloody" atmosphere, with attendees attempting to administer first aid to those injured and struggling with the dense crowd.

Tragically, the shooting resulted in the death of one rally attendee, while two others remain in critical condition. Trump himself sustained an injury, taking to social media to report being hit by a bullet in the upper part of his ear, although his campaign assured he was otherwise unharmed. The former president flew back to Newark, New Jersey, late Saturday night.

Now, the focus shifts to the ongoing investigation, which involves multiple federal and state agencies. The FBI has urged the public to provide any information they may have through a tip line or the agency's website. Photos or videos of the shooting are particularly sought after.

Crooks, a recent graduate of Bethel Park High School, was registered to vote as a Republican. Federal Election Commission records indicate that a donor named Thomas Crooks, sharing the same address, contributed $15 to a Democratic-aligned political action committee called the Progressive Turnout Project in January 2021.

Thomas' father, Matthew Crooks, expressed his bewilderment at the situation and stated he would wait to speak further until he had spoken with law enforcement officials.

Authorities faced challenges in identifying the gunman as he did not have any identification on his person. As a result, agents needed to run his DNA and conduct biometric confirmation before revealing his identity at a press conference Saturday night.

The investigation into the attack on former President Trump is still ongoing. Updates will be provided as further developments arise.