Ryan Routh, the man accused of staking out former United States President Donald Trump’s Florida golf course with a rifle, has been indicted on a charge of attempted assassination of a political candidate.

Routh, 58, was already facing two gun-related charges after he was found pointing a rifle through a fence at a West Palm Beach golf course in Florida while the Republican presidential candidate was playing a round.

“The Justice Department will not tolerate violence that strikes at the heart of our democracy, and we will find and hold accountable those who perpetrate it. This must stop,” Attorney General Merrick Garland said in a statement.

Routh has been remanded in custody ahead of his trial. The attempted assassination charge carries a maximum sentence of life in prison.

Court documents showed that the case had been assigned to Judge Aileen Cannon, a Trump appointee who in July dismissed a criminal case accusing Trump of illegally keeping classified documents after leaving office.

Routh has not yet entered a plea. His lawyers unsuccessfully sought to have him released on bond.

Prosecutors have in recent days revealed evidence they said pointed towards a plan to kill Trump.

They alleged that months before the incident, Routh dropped off a note to an unidentified person which appeared to have been premised on the idea that the assassination attempt would be unsuccessful. The note referred to his actions as a failed “assassination attempt on Donald Trump” and offered $150,000 for anyone who could “finish the job”.

They said Routh spent a month in South Florida and mobile phone data showed him near the golf course and Trump’s Mar-a-Lago Estate. He was found with a handwritten list of dates and venues where Trump had spoken or was expected to appear in August, September and October, according to court filings.

A US Secret Service agent searching the golf course ahead of Trump opened fire after spotting the partially obscured face of a man and the gun poking through the fence, prosecutors said.

The agent fired at Routh who fled. He was arrested within an hour on a Florida highway.

Routh did not fire any rounds and did not have Trump in his line of sight, officials have said, but he left behind a digital camera, a backpack, a loaded SKS-style rifle with a scope and a plastic bag containing food.

The arrest came two months after Trump was shot and wounded in the ear in an assassination attempt during a campaign rally in Pennsylvania. The Secret Service has acknowledged failings leading up to that shooting but has said that security worked as it should have to thwart a potential attack in Florida.