A deadly altercation inside Folsom State Prison has prompted officials to launch a homicide investigation after a man incarcerated at the historic prison was killed Friday evening.
The California Department of Corrections and Rehabilitation confirmed that the incident occurred around 6:28 p.m. on July 18 in the dayroom of the prison’s general population housing. According to CDCR officials, Boris Bonilla and Carlos J. Duran allegedly attacked fellow incarcerated person Brian J. Diguez. Staff responded immediately, breaking up the altercation and performing life-saving measures on Diguez.
Diguez was quickly taken to the prison’s triage and treatment area, but despite efforts by medical staff and first responders from the Folsom Fire Department, he was pronounced dead at 7:09 p.m.
No other incarcerated individuals or prison staff were injured during the attack, according to CDCR officials. Officers recovered two inmate-manufactured weapons at the scene. Bonilla and Duran were placed in restricted housing while the investigation continues.
Authorities have limited movement within the area of the prison where the assault occurred to support the ongoing investigation. The California Department of Corrections and Rehabilitation confirmed that the Folsom State Prison Investigative Services Unit is working closely with the Sacramento County District Attorney’s Office and the Sacramento County Coroner. The Office of the Inspector General was also notified. The coroner’s office will determine the official cause of death.
Diguez, 34, had been serving a 21-year sentence for voluntary manslaughter with a gang enhancement since July 25, 2016, after being convicted in Los Angeles County, according to CDCR.
Bonilla, 48, was also sentenced in Los Angeles County. He arrived at Folsom State Prison on May 17, 2012, to serve a life sentence with the possibility of parole for first-degree murder. His conviction included enhancements for the intentional discharge of a firearm causing great bodily injury or death, as well as for committing the crime in association with a street gang.
Duran, 32, came from Santa Clara County and was received on February 3, 2022. He was serving a two-year sentence for a parole violation related to vehicle theft, including prior vehicle-related theft convictions, CDCR confirmed.
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