A man serving two life sentences for murder died Saturday at Kern Valley State Prison.

The California Department of Corrections and Rehabilitation is investigating the man’s death as a homicide and the man’s cellmate has been segregated from the rest of the prison population.

Officials at the Delano-area prison identified the inmate killed as 50-year-old Alfredo Valenzuela.

Noe Herrera, 36, was segregated from prison population after his cellmate died Saturday, April 30, 2022 (California Department of Corrections and Rehabilitation)

Valenzuela had been at Kern Valley since 2010 after being convicted in Los Angeles County of two counts for first-degree murder, first-degree burglary and vehicle theft.

He was found unresponsive in his cell Saturday morning around 2:05 a.m. during a security check, prison officials said. An emergency alert was issued and he was taken to the prison’s treatment and triage center for treatment, but he was pronounced dead less than a half-hour later.

His cellmate, 36-year-old Noe Herrera, was removed from the cell and has since been rehoused at the prison’s segregation unit while they investigate Valenzuela’s death, which CDCR officials said is being treated as a homicide.

Herrera has been at the prison since August 2019 after he was convicted for second-degree murder and attempted second-degree murder in Santa Barbara County. He was serving a life sentence with the possibility of parole, CDCR said.

The Kern County Coroner’s Office will determine the cause of death.

The Kern Valley State Prison houses more than 3,200 inmates in minimum, medium and high security environments.