The Nebraska Department of Correctional Services says 36-year-old Robert Camacho died earlier this week at the Community Corrections Center-Omaha.
He was serving a 15-to-20-year sentence for First-Degree Arson out of Douglas County, and his sentence started in April of 2016.
The cause of death has not yet been determined.
A grand jury will conduct an investigation, which is required by Nebraska law whenever someone dies in custody, or while being taken into custody by law enforcement.
(Picture from Nebraska Department of Correctional Services)