Castro, 53, was found hanged in his cell around 9:20 p.m. ET Tuesday at the Correctional Reception Center in Orient, a community south of Columbus in central Ohio, JoEllen Smith, of the Department of Rehabilitation and Correction, said early Wednesday.
Prison medical staff performed CPR before Castro was transported to a hospital, where he was pronounced dead. He was in protective custody because of the notoriety of his case, meaning he was checked every 30 minutes, but was not on suicide watch, which entails constant observation, Smith said.
Castro was also watched closely in Cuyahoga County Jail in the several weeks after his arrest and before his case was resolved by a guilty plea, with logs noting his activity every 10 minutes. He was taken off county jail suicide watch in early June after authorities determined he was not a suicide risk.
Castro's attorneys tried unsuccessfully to have a psychological examination of Castro done at the Cuyahoga County Jail, where Castro was housed before he was turned over to state authorities following his conviction, his attorney, Jaye Schlachet, told The Associated Press early Wednesday. Schlachet said he could not immediately comment further.
In an interview last month after Castro's conviction, Schlachet and attorney Craig Weintraub said their client clearly fit the profile of sociopathic disorder and that they hoped researchers would study him for clues that could be used to stop other predators.
Call for help
The three women disappeared separately between 2002 and 2004, when they were 14, 16 and 20 years old. They escaped from Castro's Cleveland home May 6, when Amanda Berry, one of the women, broke part of a door and yelled to neighbours for help.
"Help me," she said in a 911 call. "I've been kidnapped, and I've been missing for 10 years and I'm, I'm here, I'm free now."
The two other women were so scared of Castro that they held back initially even as police officers began to swarm the house. But quickly they realized they were free.
"You saved us! You saved us!" another of the captives, Michelle Knight, told an officer as she leaped into his arms. Castro was arrested that evening.
Elation over the women's rescue soon turned to shock as details emerged about conditions of their captivity. Investigators say they were bound with chains, repeatedly raped and deprived of food and bathroom facilities. Knight told investigators she was beaten and starved several times to force her to miscarry.
Messages left for the women's lawyers were not immediately returned early Wednesday.
Castro was sentenced Sept. 1 to life in prison plus 1,000 years on his guilty plea to 937 counts including kidnapping and rape.
In a rambling statement, he told the judge he was not a monster, but a man suffering from a pornography addiction.
Knight was the only one of the three who appeared in court at his sentencing.
"You took 11 years of my life away, and I have got it back," she said in the hushed courtroom during her victim impact statement. "I spent 11 years in hell. Now your hell is just beginning."
This is the second high-profile suicide in an Ohio prison in a month.
On Aug. 4, death row inmate Billy Slagle was found hanged in his cell just days before his scheduled execution. He was condemned to death for fatally stabbing a neighbour.
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