Associated Press - November 9, 2009 4:45 PM ET

LINCOLN, Neb. (AP) - A man serving life sentences for murdering two women in central Nebraska in the 1970s has died at the state penitentiary.

Department of Corrections spokesman Win Barber said Monday that Dennis Sell died Saturday. Barber said it's believed Sell died of natural causes but an autopsy will be performed. Sell was 64.

Sell pleaded guilty to second-degree murder in the deaths of Judith Dangler of Lexington and Ruth Eby of Overton. He also admitted to raping Eby. He began serving his two life sentences in 1978.

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