DELANO, Calif. (KGET) — An inmate from Tulare County housed inside Kern Valley State Prison has died after he was attacked by two other inmates behind bars, according to the California Department of Corrections and Rehabilitation (CDCR).

State officials are investigating the death of 41-year-old Isaac Duran as a homicide, the department announced Saturday.

CDCR said two inmates, identified as 57-year-old Roland C. Corona from Fresno County and 33-year-old Luis Alvidrez from San Diego County, allegedly attacked Duran with an inmate-manufactured weapon at 2:55 p.m. on Tuesday, Oct. 14. Duran sustained multiple stab wounds and was transported to outside medical for a higher level of care.

According to CDCR, Duran was later pronounced dead on Thursday, Nov. 9 at approximately 9:14 p.m. while under the care of medical staff at Kern Medical Center. No staff or additional incarcerated people were injured.

Both suspects have been moved to restricted housing pending investigation into this case, CDCR said. An investigation is being conducted by Kern Valley State Prison’s Investigative Services Unit, the Kern County District Attorney’s Office and the Kern County Coroner.

The Office of the Inspector General was notified, and the Kern County Coroner will determine Duran’s official cause of death, CDCR said.