VALLEJO (AP) — A California man once sentenced to death for killing two people in the 1960s was under arrest Thursday after police said he led officers to the body of his 89-year-old mother.

Investigators said Dennis Stanworth, 70, called Vallejo police just before noon Wednesday and said he had killed his mother at his home.

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Stanworth led officers to the body of Nellie Turner Stanworth. Investigators wouldn’t say how she was killed.

Lt. Jim O’Connell said in a news release that Stanworth was arrested for investigation of murder and booked into the Solano County Jail.

Stanworth was sentenced to death in 1966 after being convicted of two counts of murder for kidnapping, sexually assaulting and shooting two teenage girls in Contra Costa County.

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The California Supreme Court reversed his death sentence in 1969 after finding 12 prospective jurors were dismissed because they said they opposed the death penalty. The U.S. Supreme Court ruled a year earlier that such jurors shouldn’t be automatically excluded from a death penalty case unless they make clear they can’t impose capital punishment under any circumstance.

Stanworth was sentenced to death again after a second trial. But in 1974, his death sentence was converted to life in prison along with 107 other California Death Row inmates including Charles Manson when the state Supreme Court struck down capital punishment. California reinstated the death penalty in 1978, but those former death row inmates such as Stanworth and Manson kept their life sentences.

State Department of Corrections and Rehabilitation records show Stanworth was released from prison on parole in 1990. The documents show him released from parole in 1993, though he was still required to register as a sex offender.

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(Copyright 2013 The Associated Press.)