SACRAMENTO (AP) – A 74-year-old sex offender sentenced to death for killing a woman and three of her children has died on death row, California corrections officials said Tuesday.

Richard Allen Benson was found unresponsive alone in his San Quentin State Prison cell early Monday and pronounced dead about a half-hour later. Officials said foul play is not suspected, though his cause of death will be determined by the Marin County coroner.

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He was sentenced to death for four counts of first-degree murder in the 1986 slayings of Laura Camargo and three of her children in San Luis Obispo County.

The parolee killed the woman first with a claw hammer, then suffocated her son, KPIX-TV said. He molested her two daughters for two days before also killing them with a hammer.

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Two additional sentences for lewd and lascivious acts on a child under age 14 and of arson of an inhabited structure were put on hold.

His trial was moved to Santa Barbara County because of pre-trial publicity.

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Copyright 2021 The Associated Press.