The report by the Department of Rehabilitation and Correction said there is "no known, substantiated motive" for Castro to kill himself, The (Cleveland) Plain Dealer reported. It suggested Castro may have hanged himself accidentally during an act of "auto-erotic asphyxiation."
Castro, who had been sentenced to life plus 1,000 years, was found dead in his cell at the Correctional Reception Center in Orient, Ohio, Sept. 3. He kept his victims in his house in Cleveland for years, raping and physically abusing them.
The report found fault with corrections officers. While officers were supposed to check on Castro every 30 minutes, footage from security cameras showed they missed several rounds in the hours before his death.
Investigators found evidence officers had falsified their log books.
Items found in Castro's cell showed he believed something was being put in his food and that he complained of the treatment he received from guards and his fellow inmates. But the report said there was no hard evidence he was contemplating taking his own life.
Castro's pants and underwear had been pulled down and were hanging from his ankles, the report said.
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