PORTLAND — An Augusta man pleaded guilty Friday in federal court to unlawful possession of a gun with a previous felony charge.

According to a trial brief filed by prosecutors in March, Augusta police encountered Raymond Lilly, 41, in Augusta’s Mill Park near a tent he lived in on Aug. 25, 2023. Police ordered him to leave the encampment by the next day or face arrest for trespassing.

Upon meeting Lilly at the park again on Sept. 1, the brief said, Lilly showed police to his tent, where he unzipped the entrance, revealing a bottle of pills that he claimed belonged to a friend of his.

Lilly was then arrested for criminal trespass, unlawful possession of a scheduled drug and failure to provide correct name and date of birth; Lilly had identified himself as “Nemo Canem” to police, the brief said.

Nemo Canem is Latin and it means nobody dog.

Police searched the tent further, finding ammo and a .22-caliber AR-15 pattern rifle, which had “seemingly intentional scratch marks across” the serial number. Lilly had two previous felony firearms convictions that prevented him from legally possessing a gun, including a conviction in 2012 for possessing an unregistered firearm.

Lilly faces a maximum punishment of 15 years in prison, a $250,000 fine and supervised release of up to three years — although the plea agreement recommended Lilly’s prison term should not exceed five years.

A news release from the U.S. Attorney’s Office for the District of Maine said a federal district court judge will determine a sentence in the coming weeks, following a presentence investigative report by the U.S. Probation Office.

The federal Bureau of Alcohol, Tobacco, Firearms and Explosives investigated the case with the Augusta Police Department.