BOISE, Idaho -

The Ada County Sheriff's Office is investigating the death of an inmate at a maximum security men's prison south of Boise.

The Idaho Department of Correction in a statement Tuesday says it requested the investigation following the death of 62-year-old Roger Vincent Arellano.

The agency says Arellano was found unresponsive in his cell at 5:21 a.m. Tuesday at the 516-bed Idaho Maximum Security Institution.

The agency says it asks the sheriff's office to investigate all unattended deaths of inmates at the facility.