LINCOLN, Neb. -- An inmate at the Reception and Treatment Center (RTC) was pronounced dead Friday.

Officials said 56-year-old Randall Dasher died while serving out his sentence at RTC. No cause of death has been determined at this time but Dasher was reportedly being treated for a medical condition prior to his death.

According to court documents, Dasher was serving a sentence of 11 years 38 months to 29 years 18 months. He was convicted of multiple theft charges, possession of a controlled substance, criminal impersonation and escape out in Sarpy, Douglas and Lancaster Counties. He started his sentence on May 11, 2009.

As is the case whenever an inmate dies in the custody of the Nebraska Department of Correctional Services (NDCS), a grand jury will conduct an investigation.