Updated

A federal judge on Monday ordered Ryan Routh, the man accused in connection with an assassination attempt against former President Trump earlier this month, held in custody. 

Magistrate Judge Ryon McCabe granted the government’s request to detain Ryan Routh pending the resolution of charges during a court hearing in Florida. Routh, who was clad in a blue prison jumpsuit and shackled by his hands and feet, appeared engaged and paid attention during the hearing. 

Prior to the court proceeding, the Justice Department asked the United States District Court for the Southern District of Florida to keep Routh in pretrial detention. McCabe said federal prosecutors met their burden and the weight of the evidence was strong.

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Ryan Routh's alleged hiding spot in Florida near Trump golf course

A general view of the fenced area near the sixth hole of Trump International Golf Club in West Palm Beach, Florida, on Wednesday, Sept. 18. The area is where Ryan Routh is reported to have lay in wait for former President Trump on Sunday. (Peter Burke/Fox News Digital/Palm Beach County Sheriff’s Office)

Routh has been charged federally with possessing a gun with a scratched-out number and with possessing a gun illegally as a felon, though more serious charges are likely pending. 

Federal prosecutors also told the judge that the government intends to ask a grand jury to indict Routh on the much more serious charge of the attempted assassination of Trump, which carries a maximum sentence of life in prison.

In addition, prosecutors said they have an audio recording of a recent jailhouse phone call from Routh to a female friend. During the call, Routh said he was "sorry," while the friend said she was still "processing" what happened. 

A court sketch depicts Ryan Routh as he appears in federal court in West Palm Beach

A court sketch depicts Ryan Routh as he appears in federal court in West Palm Beach, Florida on Monday, September 23, 2024. Routh is facing charges related to the alleged attempted assassination of former President Donald Trump last week. (Lothar Speer)

"You did the worst thing you could have possibly done," she told Routh, prompting a second apology. 

Routh will likely face additional charges in the coming days, which could include aggravated assault for allegedly pointing the rifle at a U.S. Secret Service agent and making threats against a former president, State Attorney Dave Aronberg previously told Fox News Digital. 

In addition to the federal case against Routh, the state of Florida is also investigating the suspected assassination attempt. Florida Gov. Ron DeSantis said in a press conference last Tuesday that Florida will pursue more charges against Routh and that his offense should merit life in prison.   

In a letter dated Monday to FBI Director Christopher Wray and U.S. Attorney Markenzy Lapointe, Florida Attorney General Ashley Moody asked them not to bring a specific charge against Routh, otherwise it would suspend the state's investigation. 

In a statement, Trump said the federal government has mishandled the Routh case and prefers Florida take it over, calling the charges against Routh a "slap on the wrist" while stating the Justice Department and FBI are conflicted because of the prosecutions against him. 

"If the DOJ and FBI cannot do their job honestly and without bias, and hold the aspiring assassin responsible to the full extent of the Law, Governor Ron DeSantis and the State of Florida have already agreed to take the lead on the investigation and prosecution," Trump said in a statement. 

A court sketch depicts Ryan Routh as he appears in federal court in West Palm Beach

A court sketch depicts Ryan Routh's appearance in federal court in West Palm Beach, Florida on Monday, September 23, 2024. Routh is facing charges related to the alleged attempted assassination of former President Donald Trump last week. (Lothar Speer)

"Florida charges would be much more serious than the ones the FBI has announced," he added. "The TRUTH would be followed, wherever it leads. OUR JUSTICE SYSTEM IS CORRUPT AND DISCREDITED, especially as it pertains to the 45th President of the United States, Donald J. Trump. LET FLORIDA HANDLE THE CASE!"

"To be clear, I believe it would be a grave mistake for the federal government to invoke this provision, and I urge you to cooperate with the State's investigation rather than frustrate it," Moddy wrote. 

Routh is accused of targeting the 45th president as he waited about 12 hours outside a golf club where Trump was playing a round. 

McCabe said it appeared Routh was stalking Trump for 30 days and had a passport with him when he was caught along with a phone, which had a search history of how to travel from Palm Beach County to Mexico.

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rifle aimed through fence with two bangs hanging nearby

Ryan Routh camped out near the Trump International Golf Course in West Palm Beach with an SKS-style rifle, a backpack, and a shopping bag. The two bags both contained plates capable of stopping small arms fire, a preliminary ballistics testing showed.

Federal prosecutor Mark Dispoto described Roth’s location next to the sixth hole, with the gun and bags as "nothing short of a sniper’s nest." Dispoto also said the two bags next to the gun, which had plates, or tiles in them which were bulletproof, was part of an effort to protect himself if Secret Service agents returned fire.

On Monday, the Justice Department also released a chilling letter written by the suspect. 

The Justice Department obtained the letter from a witness who says they received it inside a box delivered to them by Routh several months prior to the assassination attempt. Authorities say the witness opened the box only after hearing Routh was suspected in the attack. 

A court sketch depicts Ryan Routh as he appears in federal court in West Palm Beach

A court sketch depicts Ryan Routh's appearance in federal court in West Palm Beach, Florida on Monday, September 23, 2024. Routh is facing charges related to the alleged attempted assassination of former President Donald Trump last week. (Lothar Speer)

The box contained several handwritten letters as well as ammunition, among other things. One of the letters, addressed "Dear World," discussed the assassination attempt. 

Routh had written in the letter that he had failed and that he would give $150,000 to anyone who could finish the job. 

In a court filing, prosecutors also referred to Routh's conviction for possession of a weapon of mass destruction in 2002. They told McCabe that the device was a "binary explosive device" with a fuse.

FBI investigators carry a box of evidence from the perimeter of Trump International Golf Club in West Palm Beach

FBI investigators carry a box of evidence from the perimeter of Trump International Golf Club in West Palm Beach, Florida on Monday, Sept. 16, 2024. Ryan Routh was arrested earlier this week after allegedly attempting to assassinate former President Donald Trump while hiding in the bushes along the golf course. (Mega for Fox News Digital)

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At one point during Monday's hearing, Routh smiled while his public defender argued that the majority of his 100-plus arrests were non-violent, including passing bad checks and the theft of sinks from construction sites.

Fox News’ Anders Hagstrom, Jake Gibson, David Spunt and Danamarie McNicholl contributed to this report.