He had been housed since August 1999 in a substance abuse treatment facility at the Corcoran State Prison in central California.

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Manson has been an inmate in the 24-cell protective housing unit of the California State Prison Corcoran since 1989, said Thornton, the Department of Corrections and Rehabilitation spokeswoman.

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Last October, Manson was found to be in possession of an inmate-manufactured weapon and he is now being held for 15 months in isolation in a secured housing unit in the California State Prison Corcoran, said Commissioner Gilbert Robles, the other member of the two-person parole panel.

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