SANTA CRUZ, Calif. (KRON) — Herbert W. Mullin, a serial killer who confessed to murdering 13 victims in the early 1970s, died Thursday while in state custody.

Mullin, 75, likely died from natural causes, California Department of Corrections and Rehabilitation officials said. At the time of his death, Mullin was incarcerated in Stockton, Calif. at California Health Care Facility, a prison for patients with long-term medical needs or acute mental health disorders.

A San Joaquin County Medical Examiner will determine his official cause of death.

Mullin was a 25-year-old Felton resident when he began preying on victims around Santa Cruz. He killed an entire family who lived next to The Mystery Spot, and murdered a priest inside a confessional booth of a Los Gatos church. His victims, who ranged in age from 4 to 73, were all murdered within a matter of months.

Then-Santa Cruz County District Attorney Peter Chang said Mullin knew many of his victims before he decided to kill them. Chang described Mullin as a “psychopathic killer,” according to the Valley Press newspaper.

Herbert W. Mullin
Herbert W. Mullin confessed to a 1970s murder spree. (CDCR)

Mullin was denied parole last year. District Attorney Jeff Rosell said the serial killer has never shown “true remorse for these brutal murders” and “continues to blame others for his actions.”

During his 2021 parole hearing, Mullin blamed his parents, his sister, and numerous family members. He insisted that his parents forced him to become a killer because of how they raised him as a child.

Rosell told the parole board that Mullin should not be freed due to the number and magnitude of his crimes, their senseless and horrific nature, and the risk he would pose to the community if he were released.