Ariel Castro, the man convicted of kidnapping three women and keeping them hostage in his Cleveland, Ohio, home for a decade, committed suicide by hanging himself with a bed sheet, Franklin County Coroner Dr. Jan Gorniak ruled on Wednesday after an autopsy.
Castro, 53, was found hanged in his cell around 9:20 p.m. Tuesday at the Correctional Reception Center in Orient, Ohio, officials with the state's Department of Corrections said.
Prison medical staff tried to perform CPR on Castro but he was pronounced dead at a local hospital at 10:52 p.m.
Castro's family has demanded a full investigation into the incident.
“We're going to get to the bottom of it. There's no way we're going to let this go,” Castro’s lawyer Craig Weintraub told NBC’s “Today” show.
“This is a human being, we are in a civilized society and we expect that the person would be protected when they’re institutionalized, and so there is an obligation on the part of the prisons and I would doubt that the prison officials would dispute that. They have an obligation to ensure there wasn’t a suicide or anything else and we pray there wasn’t anything else.”
Castro was serving a life sentence plus 1,000 years for the kidnap, rape and assault of three young women. Michelle Knight was abducted in 2002, Georgina DeJesus in 2004, and Amanda Berry in 2003.
The women made a daring escape on May 6 after Berry broke out with the help of a neighbor while Castro was out of the house.
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Castro pleaded guilty to more than 900 charges in connection with his three captives' ordeal, including rape and murder.
He had been serving his sentence in a cell set apart from the general prison population.
"He was housed in protective custody which means he was in a cell by himself and rounds are required every 30 minutes at staggered intervals," JoEllen Smith of the the Ohio Department of Corrections told CNN in a statement.
"A thorough review of this incident is underway," she added.
A cousin of Castro said the man's death may be for the best.
"Really what was he suffering behind bars. I mean getting three square meals a day. Sleeping in a nice, warm, soft bed. Being basically watched over and guarded. Making sure that he was safe,” Maria Castro Montes told CNN's "New Day" show.
“You know those girls didn’t even have that luxury when they were being held captive in his home.”