SAN QUENTIN (CBS SF) — A death row inmate who was condemned for a Southern California crime spree that included multiple rapes and murder has been found dead in his cell at San Quentin State Prison, officials said Tuesday.

Stevie Lamar Fields, 60, was pronounced dead at 6:05 a.m. after he had been found unresponsive in his cell. Lifesaving measures were initiated, but Fields passed away. The cause of death was unknown pending the results of an autopsy.

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Fields was sentenced to death by a Los Angeles County jury for a crime spree which occurred in Los Angeles from September 28, 1978, to October 5, 1978.

He was convicted for the kidnapping, robbery, rape and murder of 26-year-old Rosemary Janet Cobb.

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Fields was also convicted of the kidnapping, robbery and rape of Gwendolyn Elaine Barnett, Cynthia Marie Smith and Colleen Coats and the robbery of Clarence Gissendander.

Fields had been on California’s death row since August 27, 1979.

Since 1978, when California reinstated capital punishment, 71 condemned inmates have died from natural causes, 25 have committed suicide, 13 have been executed in California, one was executed in Missouri, one was executed in Virginia, eight have died from other causes, and four (including Fields) causes of death are pending.

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There are currently 750 offenders on California’s death row.