STILLWATER, Minn. (AP) — A Minnesota inmate serving time for murder has been charged in the death of a corrections officer at the prison last month.

Prosecutors charged 42-year-old Edward Muhammad Johnson on Thursday with second-degree murder and second-degree assault. He is scheduled to appear in court Friday.

Johnson is accused of fatally beating 45-year-old Officer Joseph Gomm with a hammer at Stillwater state prison on July 18.

According to the complaint, Johnson is accused of bludgeoning Gomm with a hammer that Johnson had checked out of the prison shop. Gomm also was stabbed with a homemade knife.

Johnson also is accused of swinging the hammer at a corrections employee who is a prison shop foreman.

Johnson was serving a 29-year sentence for fatally stabbing his roommate in 2002.

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