Deputies at the West Valley Detention Center in Rancho Cucamonga found inmate Zacarias Joseph Ruiz, 38, unconscious in his cell on January 19, 2026. According to the San Bernardino County Sheriff’s Department, Ruiz showed signs of trauma when discovered around 11:12 p.m. Jail staff and emergency medical personnel attempted lifesaving measures before transporting him to a hospital, where he was pronounced dead the following day.
Detectives from the Sheriff’s Specialized Investigation Division – Homicide Detail responded and began an investigation. They determined that Ruiz and his cellmate, Isaiah Mark Bailon, 26, had been involved in a physical altercation prior to deputies finding Ruiz.
Bailon has been in custody since December 31, 2025, after being arrested by Hesperia Station deputies for attempted murder and robbery. He has now been additionally booked for murder related to this incident.
Ruiz had been incarcerated since May 5, 2025, following his arrest for criminal threats and domestic violence. An autopsy is scheduled to determine the official cause and manner of death.
“This investigation is ongoing and anyone with information related to this case is asked to contact the Homicide Detail at 909-890-4904. Callers wishing to remain anonymous should contact We-Tip at 1-800-78-CRIME (27463) or go to wetip.com,” stated Detective E. Badillo.
The San Bernardino County Sheriff’s Department provides law enforcement services across the largest county by area in the contiguous United States and supports over 2.1 million residents through its divisions such as patrol, detention facilities like West Valley Detention Center, aviation units, training programs, and a public safety dispatch center. The department operates under the leadership of Sheriff-Coroner Shannon D. Dicus and maintains a focus on integrity and professional service delivery according to its official website.
Shannon D. Dicus serves as sheriff-coroner for the department which manages multiple patrol stations throughout San Bernardino County—the largest geographical county in the contiguous U.S.—and offers collaborative law enforcement services tailored to community needs (source).
