VACAVILLE (CBS SF) — One of the infamous “Zebra Killers” who terrorized San Francisco residents in the early 70s has died at a prison hospital, corrections authorities announced Thursday.

Jessie Lee Cooks, 76, was found unresponsive in his bed at the hospice unit of the California Medical Facility in Vacaville Wednesday night, the California Department of Corrections and Rehabilitation said. His cause of death will be determined by the Solano County Coroner.

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Jesse Lee Cooks (CDCR)

Cooks was sentenced to life in prison in 1976 with the possibility of parole for first-degree murder, kidnapping, and first-degree robbery. He along with three other Black Muslim men were convicted in a string of racially-motivated killings in San Francisco between October 1973 and April 1974.

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At least 15 people were killed and eight wounded in the attacks and some authorities believe they may be behind dozens of other killings. They were dubbed the Zebra murders after the special police radio band assigned to the investigation.

Among those wounded was future San Francisco Mayor Art Agnos who was shot twice in the chest in 1973.

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Of the other three Zebra killers, J.C.X. Simon died at San Quentin State Prison in 2015 at theage of 69. Manuel Moore died at the California Health Care Facility in Stockton in 2017 at the age of 73. Larry Green, 69, is still incarcerated at California State Prison-Solano in Vacaville.