75-year-old Joseph S. Cordova, who was sentenced to death in 2007 for the 1979 rape and murder of 8-year-old Cannie Melinda Bullock in San Pablo, was found unresponsive in his single cell Wednesday afternoon.
Cordova was pronounced dead at the scene.
According to officials, there were no signs of trauma.
His cause of death is yet to be determined by the coroner.
Cordova had been on death row since 2007.
San Quentin State Prison is currently the site of a massive coronavirus outbreak, with more than a thousand inmates having tested positive for the virus. More than a hundred staff members have also contracted the virus.
State officials have placed medical tents on the baseball field at San Quentin, but at this point it is unknown if they will be used to triage patients, isolate those who are COVID positive from those who are not, or to actually treat patients in a field hospital-like setting.
Last week, another death row inmate, 71-year-old Richard E. Stitely, was found dead. He had tested positive for coronavirus.
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