MEMPHIS, Tenn. (AP) -- A Memphis gun dealer has been sentenced to life in prison without parole after a federal prosecutor revealed he bludgeoned to death a Baltimore doctor three years before the killing of a code enforcement officer.

Dale Mardis received the sentence Tuesday in the killing of code enforcement officer Mickey Wright in what the government called a federal hate crime.

Prosecutor Steve Parker made a stunning revelation when he said Mardis admitted last week to killing Dr. Henry Ackerman in June 1998 in Memphis.

Parker said Mardis agreed to plead guilty to first-degree murder in the doctor's slaying in both federal and state court.

Mardis didn't speak at the hearing.

He had already pleaded guilty to violating the civil rights of Wright, who was black, by killing him and disposing of his body. Mardis is white.

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