The Nebraska Department of Correctional Services says 58-year-old Whitney Hopkins died shortly after 11 a.m. Monday at Bryan West Medical Center-West.

Hopkins was serving a nine-year sentence at the Nebraska State Penitentiary for convictions of drug possession and distribution, child abuse and tampering with a witness in Gage County. He was transferred to the Diagnostic and Evaluation Center on Wednesday and driven to the hospital Monday morning due to an unspecified medical issue.

Officials say the cause hasn’t been determined, but Hopkins was being treated for a medical condition.

A grand jury will investigate, as happens with all inmates who die in custody.