SIOUX FALLS, S.D. (AP) — State prison officials say an inmate serving a life sentence for first-degree murder has been found dead in his cell.

Authorities say 37-year-old Kent Davidson was found dead at the South Dakota State Penitentiary early Monday morning.

Authorities say the death is under investigation by the Division of Criminal Investigation. An autopsy will be conducted.

Davidson was serving a life sentence out of Brule County for first-degree murder. He was also serving a five-year sentence for forgery out of Tripp and a five-year sentence for second-degree escape out of Minnehaha County.

The death brings to three the number of inmates who have died at the prison in the past week.

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