LEXINGTON, Neb. (AP) – Authorities in south-central Nebraska are investigating the death of a teenage inmate at the Dawson County Jail in Lexington.

The 18-year-old was found unresponsive in his cell Friday night.

Officials say medical aid was rendered to the inmate and he was rushed to a local hospital, where he was pronounced dead. An autopsy has been ordered.

Neither the Dawson County Sheriff’s Office nor the Dawson County Attorney had released the inmate’s name by midday Tuesday.

Under state law, a grand jury must be convened to investigate whenever a person dies in jail or in the custody of a law enforcement officer.