KEARNEY, Neb. — Authorities are investigating the death of a 38-year-old inmate at the Buffalo County Jail after he was found unresponsive in his cell Tuesday afternoon.

According to the Buffalo County Sheriff’s Office, Jhett Henderson of Kearney was found at around 4:13 p.m. where jail staff attempted life-saving measures.

Henderson was transported to CHI Good Samaritan Hospital where he was later pronounced dead.

Henderson was in custody on six charges of terroristic threats.

Nebraska law requires a grand jury investigation when a death occurs in law enforcement custody, and the Buffalo County Attorney has also ordered an autopsy.

The South Central Area Law Enforcement Services, or SCALES, is leading the investigation which remains ongoing.