Officials say 41-year-old Jonathan Watson attacked two other inmates with a weapon, causing severe injuries to their heads.
As both men were rushed to a local hospital, 48-year-old David Bobb died from his injuries. State prison officials say he was serving a life sentence for aggravated sexual assault of a child.
The second inmate is in critical condition at the hospital. His name has not been released.
Investigators are working to determine what led up to the attack. Watson is currently serving prison time for a previous first-degree murder.
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