Judge detains Ryan Routh after prosecutors say Trump stakeout was an 'assassination attempt'

(This story was updated to add new information.)

A federal magistrate ordered Ryan Routh detained until trial on gun charges over a golf-course incident with former President Donald Trump that prosecutors said Routh described in a handwritten note as “an assassination attempt” that failed.

U.S. Magistrate Judge Ryon McCabe ordered Routh detained without bond after a three-hour hearing in Florida, where federal prosecutors linked him to the rifle found at Trump International Golf Club. Routh’s cellphone was tracked near the golf course and Trump’s Mar-a-Lago estate in the month before his arrest Sept. 15, according to a court filing by prosecutors.

Routh was arrested after a witness saw him leaving the golf course while Trump was playing. A Secret Service agent fired several shots at a suspect who leveled a rifle from the foliage along the sixth hole. FBI agents found an SKS semiautomatic rifle loaded with 12 rounds of ammunition where Routh was allegedly hiding.

Routh allegedly left the handwritten letter in a metal box with someone, who wasn’t named in the court filing from prosecutors, months before the incident at the golf course. The witness opened the box after hearing about Routh's arrest, and law enforcement visited the person Sept. 18. The box also contained ammunition, a metal pipe, building materials, four phones and several letters, prosecutors said.

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“This was an assassination attempt on Donald Trump but I failed you,” said the letter, a picture of which appears in the court filing. “I tried my best and gave it all the gumption I could muster. It is up to you now to finish the job; and I will offer $150,000 to whomever can complete the job.”

Routh, 58, has been charged with possession of a firearm despite being a convicted felon and possession of a weapon with an obliterated serial number. The revelations about handwritten note come as prosecutors could enhance the charges against Routh to include attempted assassination.

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Trump issued a statement saying the charges in the case against the “aspiring assassin” are “a slap on the wrist.” He is skeptical the Justice Department and FBI are pursuing the case aggressively and said state prosecutors in Florida should handle the case.

“Florida charges would be much more serious than the ones the FBI has announced,” Trump said.

Routh had a detention hearing scheduled at 11 a.m. Monday, where prosecutors seek to keep him locked up until trial. He has not yet entered a formal plea, which is scheduled Sept. 30.

The court filing contained other allegations intended to link Routh to the gun and to stalking Trump.

The FBI found a fingerprint on tape attached to the SKS rifle that preliminarily matched Routh.

The FBI’s analysis of Routh’s phone showed that he traveled from the area around Greensboro, North Carolina, to West Palm Beach, Florida, on Aug.14. On multiple days and times from Aug. 18 to Sept. 15, Routh’s phone accessed cell towers near Trump International Golf Club and the former president’s residence at Mar-a-Lago.

After local authorities pulled Routh over in a black Nissan Xterra seen leaving the golf course, officers discovered license plates didn’t belong to the vehicle. FBI agents found two additional license plates inside, along with six cellphones, 12 pairs of gloves, a Hawaii driver’s license, a passport and a handwritten list of dates in August, September and October where the former president had been or was expected.

One of the cellphones contained a search query asking how to travel from Palm Beach County to Mexico.

This article originally appeared on USA TODAY: Judge detains Ryan Routh in Trump stakeout 'assassination attempt'