A Glenburn man faces a potential lengthy prison term after pleading guilty Monday to being a felon in possession of a firearm.

Jonathan Gardner, 31, entered his guilty plea in U.S. District Court in Bangor.

In November 2014, law enforcement officials said they found a 12-gauge shotgun in Gardner’s attic and a 9-mm pistol on the ground behind his house. They said tests indicated that Gardner had handled both weapons.

Gardner had previously been convicted for burglary, aggravated assault, theft and drug trafficking and was prohibited from possessing firearms.

If Gardner is found to be an armed career criminal, he would face 15 years to life in prison, five years of supervised release and a fine of up to $250,000.

He has yet to be sentenced.