Updated

Federal prosecutors announced gun charges Friday 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 convicted 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 that 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.

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

Investigators said Friday that Gilliam used a photo provided by police to identify Kazemi as the person who bought the gun. Gilliam was assigned a public defender at a hearing Friday afternoon, but a hearing to set bond was delayed until Wednesday.

"No one denies this is a tragedy," Gilliam's public defender Hugh Mundy said. "Steve McNair was one of Nashville's heroes. A lot of lives have already been ruined. But Mr. Gilliam is a decent, hard-working family man and there's no reason to ruin his life too."

Detectives traced the gun, a 9 mm Bryco/Jennings, to its 2002 sale at a pawn shop, 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. Nashville Police Chief Ronal Serpas said at a news conference of federal and local officials Friday that Gilliam decided to sell the gun because his wife was afraid to have it in their house.

Gilliam was in federal custody awaiting his initial court appearance Friday afternoon. It wasn't immediately clear if he has an attorney.

Police said last week that Kazemi purchased "a fully loaded 9 mm pistol from a private individual" who met her in the parking lot of the mall where she worked at a Dave & Busters restaurant.

Kazemi met Gilliam when she was trying to sell her car. She mentioned to him that she was looking to buy a gun and he told her he had one for sale, police said. The sale took place two days before McNair's shooting, outside the restaurant where Kazemi worked and first met McNair.

Authorities believe McNair was asleep when Kazemi put the pistol to his head and pulled the trigger. She put two more slugs into his chest and a fourth bullet into the other side of his head before shooting herself.

McNair, a married father of four, walked away from the NFL last year. "Air McNair" was known as a gutsy quarterback who played through serious injuries and led his Tennessee Titans to a Super Bowl.

U.S. Attorney Edward Yarbrough said Kazemi's age did not make the sale of the gun illegal. A licensed dealer is barred from selling a gun to someone younger than 21, but private sales to people older than 18 are legal, he said.

Yarbrough said one of the top objectives of federal gun laws prohibiting felons from possessing guns is "to thwart and prevent violent crime such as the two deaths in this case."

Jim Cavanaugh, the ATF special agent in charge in Nashville, held up a pistol similar to the one used to kill McNair, and said, "A convicted felon cannot receive it, possess it, buy it, store it, hold it, shoot it, aim it, clean it, or do anything with it."

Though the gun sale in question did not involve a licensed gun dealer, the ATF recently warned all gun dealers in Tennessee that they must still comply with federal gun laws despite a new state law aimed at easing such requirements for weapons manufactured and sold in-state.