Trump Jr. says father is 'changed man'

The man suspected of taking aim at former President Donald Trump Saturday night was a member of a local shooting club, counsel for the club confirms to ABC News.

Thomas Crooks belonged to Clairton Sportsmen's Club, in Clairton, Pennsylvania, roughly 12 miles south of Pittsburgh, which has a variety of shooting ranges.

"I can confirm that Mr. Crooks was a member of Clairton Sportsmen's Club," Robert S. Bootay III, attorney for the club, said in a statement.

"Beyond that, the Club is unable to make any additional commentary in relation to this matter in light of pending law enforcement investigations," Bootay continued.

"Obviously, the Club fully admonishes the senseless act of violence that occurred yesterday. The Club also offers its sincerest condolences to the Comperatore family and extends prayers to all of those injured including the former President," he said.

-ABC News' Sasha Pezenik

President Joe Biden says "we can't, we must not go down" the road of political violence in American after Saturday's attempted Trump assassination.

President Joe Biden spoke directly to the nation Sunday, saying the political landscape cannot be a "killing field" after the assassination attempt against former President Donald Trump Saturday.

"Disagreement is inevitable in American democracy," Biden said, adding, "It's part of human nature."

"But politics must never be a literal battlefield or God forbid, a killing field," Biden continued.

"I believe politics ought to be an arena for peaceful debate, to pursue justice, to make decisions guided by the Declaration of Independence and our constitution we stand for in America, not of extremism and fury, but of decency and grace," Biden added.

During his address, Biden said "we can't, we must not go down" the road of political violence in the U.S. and asked Americans to "lower the temperature" in our politics.

The president also said that he spoke on the phone with Trump following the attack and that he's "grateful" Trump was not seriously injured and doing well.

Biden ended his speech with a call for unity, saying, "Let's remember we are the United States of America."

"There is nothing, nothing, nothing beyond our capacity when we do it together," he added.

Law enforcement sources tell ABC News that the FBI is currently in possession of three firearms from Saturday's shooting and defense of the former president.

The firearms include one belonging to the shooter, one belonging to the Secret Service agent who shot and killed the shooter and the other belonging to a Butler County Sheriff's Deputy who was involved in the shooting.

-ABC News' Luke Barr