California Department of Corrections and Rehabilitation (CDCR) officials are investigating the July 18, 2025 death of an inmate at Folsom State Prison (FSP) as a homicide.
At approximately 1828 hours, Inmates Boris Bonilla (AL4717) and Carlos J. Duran (BG4401), attacked Inmate Brian J. Diguez (BA5024), in the dayroom of a housing unit.
Responding officers quickly quelled the incident and immediately initiated life-saving measures on Diguez. Diguez was taken to the prison’s triage and treatment area where he was pronounced deceased by Folsom Fire Department at 1909 hours. No staff or other inmates were reported injured.
Officers recovered two inmate-manufactured weapons at the scene.
Bonilla and Duran were moved to restricted housing pending investigation into this case. Officials have limited movement in the area where the attack occurred to facilitate the investigation being conducted by FSP Investigative Services Unit, the Sacramento County District Attorney’s Office and the Sacramento County Coroner. The Office of the Inspector General was notified, and the Sacramento County Coroner will determine Diguez’s official cause of death.
Inmate Diguez, 34, was received from Los Angeles County on July 25, 2016. He was sentenced to 21 years for voluntary manslaughter with an enhancement of street gang act in commission of a serious felony.
Inmate Bonilla, 48, was most recently received from Los Angeles County on May 17, 2012. He was sentenced to serve life with the possibility of parole for first-degree murder with enhancements for intentional discharge of firearm causing great bodily injury/death and street gang act in commission of a serious felony.
Inmate Duran, 32, was most recently received from Santa Clara County on Feb. 3, 2022. He was sentenced to two years for a parole violation for vehicle theft with prior vehicle-related theft convictions.
