Marine (search) who had told authorities he had been shot while trying to help a stranded motorist has now admitted that he shot himself to avoid being shipped overseas.

The Anoka County sheriff's department said Wednesday that Adam Welter, 20, acknowledged the gunshot wound was self-inflicted. He was treated and released from a hospital Monday.

Welter was reportedly scheduled to ship out for Hawaii (search) that day. It wasn't clear where he was to be sent from there. He called an investigator Tuesday to take responsibility, said Capt. Robert Aldrich, a sheriff's department spokesman.

"He was extremely remorseful for this and the commotion he caused," Aldrich said. "I don't think he anticipated it would become as large a story as it did."

Welter told investigators he was shot in the left shoulder early Monday after stopping to help a pickup truck driver on a remote road near his home. Authorities found no blood, shell casings or other evidence at the scene. Welter also couldn't give a detailed description of his alleged assailant or the truck.

Welter's family did not answer its door or phone calls from a reporter Wednesday.

A sheriff's department statement said Welter's motive "appears to be a sense of despondency about an impending long-term overseas military assignment."

military law (search) expert said Welter, who enlisted in October, could face a court martial for faking a disability to avoid his duties.

The Anoka High School graduate had been in training for about a year and came home for two weeks before he was scheduled to ship out, Welter's mother, Valerie Welter, earlier told the Star Tribune.

Capt. Nat Fahy, a spokesman at Marine Corps headquarters in Washington, said it was not immediately clear what sort of military discipline Welter might face, if any.

The offense carries a maximum punishment of a dishonorable discharge, forfeited pay and allowances, and up to 10 years confinement.

"Because it's occurring during a time of war, the commander will not look at this very lightly," said Grant Lattin, a retired lieutenant colonel and Judge Advocate General lawyer in the Marine Corps. "They're going to consider making an example of him."

In February, a U.S. soldier in Germany admitted he shot himself in frustration over his Army career. The 26-year-old initially told police he was attacked by an unknown assailant while standing in a parking lot near his barracks.