Oct 18, 5:58 PM EDT

Man imprisoned 43 years for murder dies at penitentiary

FORT MADISON, Iowa (AP) -- Corrections officials say a convicted murderer who had been imprisoned for more than 43 years has died at the Iowa State Penitentiary in Fort Madison.

Officials announced Tuesday that 74-year-old Elbert James Hinkle was found Monday unresponsive on a restroom floor. Crews attempted CPR and rush Hinkle to a Fort Madison hospital, where he was pronounced dead.

Officials say they believe Hinkle died of natural causes but that a cause of death would need to await autopsy results.

Hinkle was serving a life sentence for 1st degree murder from Polk County. His sentence began in February 1973.

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