PORTLAND – A Rockland man was sentenced on Tuesday in U.S. District Court to 15 years in prison for illegally possessing a firearm.

Frank Mastera, 38, also was sentenced to five years of probation. He was arrested on Aug. 28, 2003, in Rockland in connection with a burglary and theft earlier in the month from a Mechanic Street home.

The rifle and ammunition Mastera admitted taking in the burglary were recovered later by Rockland police from the home of the Thomaston resident he had sold them to.

Mastera pleaded guilty in September in federal court in Portland to possession of a firearm by a felon and possession of a stolen firearm.

U.S. District Judge George Singal determined that Mastera’s prior felony convictions, including one for stalking, qualified him for status as an armed career criminal, which carries a 15-year mandatory minimum sentence in federal prison.