A man suspected of attempting to assassinate Donald Trump appeared in federal court on Monday, where he was charged with two gun-related crimes a day after being spotted with a rifle hiding in the bushes at the former US president's golf course in Florida.

More charges appear likely, but the initial counts - possession of a firearm as a convicted felon and possession of a firearm with an obliterated serial number, according to the US Justice Department - will allow authorities to keep him in custody as the investigation continues.

On Sunday, the US Secret Service opened fire after an agent saw a rifle barrel poking out of the bushes at Trump's golf course in West Palm Beach, a few hundred yards away from where the former president was playing. The gunman fled by car, leaving behind two backpacks and his weapon. A suspect, later identified as Ryan Routh, 58, was later arrested.

Routh wore dark prison scrubs and his hands and feet were shackled during an appearance on Monday morning in a federal courtroom in West Palm Beach, CNN reported.

Trump, the Republican presidential candidate in the Nov. 5 election, was unharmed but the incident raised fresh questions about how an armed suspect was able to get so close to him, just two months after another gunman fired at Trump during a July 13 rally in Butler, Pennsylvania, grazing his ear with a bullet.

The Secret Service, which protects presidential candidates, “needs more help,” including possibly more personnel, President Joe Biden told reporters on Monday morning, adding: “Thank God the president's OK.”

The agency came under intense scrutiny after the earlier attempt on Trump's life, which led to the resignation of Director Kimberly Cheatle. The service bolstered Trump's security detail following the July 13 attack, in which the gunman was shot dead by responding agents.

House of Representatives Speaker Mike Johnson, who convened a bipartisan task force to investigate after the first assassination attempt, said in a Fox News interview that Congress would also examine the latest incident.

“We need accountability,” said Johnson who also called for more resources to protect Trump. “We must demand that this job is being done.”

Secret Service Acting Director Ronald Rowe traveled to Florida after Sunday's assassination attempt, according to several news outlets. Rowe, who took over after Cheatle's resignation in July, told Congress on July 30 he was “ashamed” of security lapses in the earlier attack. Rowe has been with the 7,800-member Secret Service for 25 years, according to an official biography, rising to the agency's No. 2 spot before he was promoted in July.

Trump's Democratic opponent, Vice President Kamala Harris, said on X: “Violence has no place in America.”

SUSPECT IS UKRAINE SYMPATHIZER

Routh was a staunch supporter of Ukraine and had traveled there after Russia's 2022 invasion, seeking to recruit foreign fighters.

Profiles on X, Facebook and LinkedIn with Routh's name contained messages of support for Ukraine as well as statements describing Trump as a threat to U.S. democracy.

“@POTUS Your campaign should be called something like KADAF. Keep America democratic and free. Trumps should be MASA ...make Americans slaves again master. DEMOCRACY is on the ballot and we cannot lose,” read a post on X, tagging Biden.

Reuters was not able to confirm that the accounts belonged to the suspect, and law enforcement agencies declined to comment. Public access to the Facebook and X profiles was removed hours after Sunday’s incident.

Harris and other Democrats have cast Trump as a danger to U.S. democracy, citing his effort to overturn his defeat in the 2020 election. Harris has promised unwavering support for Ukraine if elected.

Trump has expressed skepticism about the amount of aid the U.S. has provided Ukraine and has vowed to end the war immediately if elected. He told Reuters last year that Ukraine might have to cede some territory to gain peace.

Trump blamed Biden and Harris for the assassination attempt, citing their “rhetoric” and claiming the suspected gunman was acting on Democrats' “highly inflammatory language,” though authorities have not yet offered evidence of any motive.

“Their rhetoric is causing me to be shot at, when I am the one who is going to save the country, and they are the ones that are destroying the country — both from the inside and out,” he said, according to Fox.

Elon Musk, the billionaire owner of X, posted and then deleted a message on the social media site on Sunday wondering why no one had tried to assassinate Biden or Harris. In a follow-up post on Monday, Musk, who has endorsed Trump, said he had been joking.