SAN QUENTIN (CBS13) – A death row inmate died in the hospital, prison officials say.

Dennis Duane Webb had been on death row since August 1988 for the murder of San Luis Obispo couple John and Lori Rainwater. Webb was convicted of breaking into the couple’s home, raping and killing the couple.

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Tuesday, Webb was transported to the hospital from San Quentin Prison and was pronounced dead. He was 65-years-old.

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No details about what led up to Webb dying have been released. Investigators are waiting on an autopsy report to find out his exact cause of death.

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Webb was one of the more than 700 convicts on death row. No executions have been carried out in the state since 2006.