Two inmates at Kern Valley State Prison who were transferred there from Riverside County were involved in an altercation that turned deadly for one of them, authorities said Saturday.
The altercation began around 10:30 a.m. Friday when Mario Renteria allegedly began striking Julian Mendez, according to the California Department of Corrections and Rehabilitation.
Prison staff responded, ordering the men to get down, but they allegedly both failed to comply. Staff used chemical agents, which initially stopped the attack, but over 30 additional inmates then rushed Renteria and began striking him, officials said.
Staff used multiple blast grenades to quell the violence, according to the CDCR.
Mendez received multiple wounds and life-saving measures were performed before he was taken to KVSP’s Triage and Treatment Area, where a doctor pronounced him dead at 11:05 a.m.
An improvised weapon allegedly was found at the scene.
Renteria was being held in restricted housing pending investigation, and officials have limited population movement to facilitate the investigation, which was being conducted by KVSP’s Investigative Services Unit and the Kern County District Attorney’s Office.
Mendez’s official cause of death will be determined by the Kern County coroner.
Mendez, 46, was received from Riverside County on Dec. 2, 2004. He received a condemned sentence in 2002 for the first-degree murder of two teenagers, according to the CDCR.
Renteria, 36, was received from Riverside County on April 27, 2022. He was sentenced to life with the possibility of parole for first-degree murder — a third strike offense — and arson, according to the CDCR.