Thomas Matthew Crooks identified as gunman who shot Donald Trump at Pennsylvania rally

The man who shot Donald Trump at a campaign rally has been named as Thomas Matthew Crooks .

The FBI confirmed Thomas Matthew Crooks, 20, of Bethel Park, Pennsylvania, shot Trump at the rally in Butler, Pennsylvania, on Saturday. He is now dead.

The FBI is treating the shooting as an assassination attempt.

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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 http://FBI.gov/butler or call 1-800-CALL-FBI."

The FBI said the motive is not yet known. The agency said the investigation remains active and ongoing.

One rally attendee was killed and two spectators were critically injured, authorities said. All were identified as men.

The Secret Service said it killed the suspected shooter. The attack was the most serious attempt to assassinate a president or presidential candidate since Ronald Reagan was shot in 1981.

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It drew new attention to concerns about political violence in a deeply polarized U.S. less than four months before the presidential election .

Trump plans to attend the RNC on Monday in Milwaukee. Organizers said the convention would proceed as planned.

Trump flew to New Jersey after visiting a local Pennsylvania hospital, landing shortly after midnight at Newark Liberty International Airport. Video footage posted by an aide showed the former president deplaning his private jet flanked by US Secret Service agents and heavily armed members of the agency's counter assault team in a show of force by his protective detail.