Deaths in Custody
Died in prison

Mark Squires

70 years old · died September 17, 2024 · San Quentin State Prison, Marin County, California

Mark Squires, 70, was held at San Quentin Rehabilitation Center in Marin County, California, and was found unresponsive in his cell on September 17, 2024. The California Department of Corrections and Rehabilitation says it is investigating his death as a homicide with the Marin County District Attorney's Office, and it has placed another incarcerated person in restricted housing while that investigation proceeds. Prison officials reportedly suspect his cellmate, but have not released details. He was taken to the prison's treatment area and an outside medical facility pronounced him dead at 4:04 p.m., and the Marin County Coroner will determine the official cause of death.

Cause of death, as reported: Killed by another person in custody. The California Department of Corrections and Rehabilitation says it is investigating the death as a homicide and suspects his cellmate, with the Marin County coroner yet to determine the official cause.

Reported by: California Department of Corrections and Rehabilitation (the agency that held him). The only account of how this person died comes from the agency that held him.

News reports (2)