SAN QUENTIN (CBS SF) — Condemned inmate Richard Allen Benson, a sex offender who killed a mother and her three young children in San Luis Obispo County in 1986, was found dead in his cell at San Quentin State Prison, officials said Tuesday.

Benson, 74, was found unresponsive in his cell at 5:27 a.m. Monday, according to the California Department of Corrections and Rehabilitation (CDCR).

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Richard Allen Benson (CDCR)

Prison guards performed CPR on Benson and summoned an ambulance, but Benson was pronounced  by a paramedic, CDCR said. Benson did not have a cellmate and foul play was not suspected. The Marin County Sheriff’s Office Coroner Division will determine his cause of death.

Benson was a parolee with a history of child molestation convictions when he was sentenced to death in 1987 for the murders of Laura Camargo and her three children.

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After first killing Camargo with a claw hammer and then her suffocating her 23-month-old son, Benson then molested the two daughters, ages 3 and 4, over a two-day period before also beating them to death with a hammer.

Benson then set fire to the bodies and the family’s apartment to try and cover up his crimes. His trial was moved to Santa Barbara County because of the heavy publicity in San Luis Obispo County.

There are currently 703 people on California’s death row. Governor Gavin Newsom has placed a moratorium on any executions in the state.

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