NASHVILLE, Tenn. — Federal prosecutors announced gun charges today against a convicted murderer who admitted he sold the pistol that was used to kill ex-NFL quarterback Steve McNair.

Adrian J. Gilliam Jr., 33, of LaVergne, Tenn., was arrested by agents of the Bureau of Alcohol, Tobacco, Firearms, and Explosives.

He is charged with being a felon in possession of a firearm. Conviction could bring a maximum sentence of 10 years in prison and a fine of up to $250,000, federal prosecutors said.

A criminal complaint says Gilliam, who was convicted in 1993 in Florida for murder and attempted armed robbery, told police he sold the gun to the woman who later shot McNair.

McNair was shot to death July 4 at his condo by his 20-year-old mistress, Sahel Kazemi, who then turned the gun on herself.

Investigators said today that Gilliam used a photo provided by police to identify Kazemi as the person who bought the gun.

Detectives traced the gun, a 9 mm Bryco/Jennings, to its 2002 sale at a pawnshop, according to the complaint. Gilliam eventually bought it from an individual for $100 about a year or year and a half ago. Investigators said Gilliam told them he bought the gun for protection after his home was burglarized, and police reports indicate he did report a burglary about the time of the gun purchase.

According to court documents, Gilliam told detectives he sold the gun to Kazemi for $100.