Officials at Kern Valley State Prison said on Wednesday that they are investigating the death of an inmate as a homicide.

Officials say 27-year-old Inmate Johnny R. Montenegro,was found unresponsive in his cell at approximately 3 a.m.

KVSP  officials noted that their staff immediately began lifesaving measures and an ambulance was called after the incident.

Montenegro died from his injuries and was pronounced dead at 3:48 a.m.

His next-of-kin has been notified.

Officials say that Montenegro was received by the California Department of Corrections and Rehabilitation (CDCR) on May, 2015, from San Bernardino County to serve a three-year sentence for possession of or owning a firearm by a felon.

Prison officials have named Montenegro’s cellmate, 41-year-old Renick De Anda as a suspect.

De Anda was received by CDCR back in November 2005, from LA County to serve a life-with-the-possibility-of-parole sentence for first-degree murder.

Officers have placed De Anda in the Administrative Segregation Unit pending the investigation by KVSP, the Kern County Coroner and the Kern County District Attorney. The Office of the Inspector General was notified.