An Arkansas prison inmate was found dead Sunday morning, the state Department of Correction reported Monday.

William Turner, 46, was found unresponsive in his assigned barracks at the Tucker Unit about 7:38 a.m., the department said in a news release. Emergency personnel treated Turner but he was pronounced dead at 8:31 a.m.

The state prison system and Arkansas State Police are investigating.

Turner had been serving a 25-year sentence on a drug-related conviction in Pike County, the release says.