Ariel Castro, sentenced to life in prison for holding three young women captive and raping them for a decade, has been found dead in his prison cell, news reports said.
CBS television and other US news outlets reported that the former Cleveland, Ohio school bus driver, who was sentenced to life in prison last month, was found dead in his cell late Tuesday.
The 53-year-old Castro was found hanging in his cell and officials tried to resuscitate him, according to a statement from the Ohio Department of Corrections, according to TV station KTLA of Los Angeles.
"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. Upon finding inmate Castro, prison medical staff began performing life saving measures," the statement said.
Castro was pronounced dead at 10:52 pm.
"A thorough review of this incident is underway," the statement by corrections department spokeswoman JoEllen Smith said, according to KTLA.
Smith was not immediately reachable for comment.
Castro's crime shocked the country and led to an outpouring of national pity for the three victims, who were abducted separately between 2002 and 2004.
Their names are Amanda Berry, now 27; Gina DeJesus, 23; and Michelle Knight, 32.
They ranged in age from 14 to 20 when they were abducted off the street by Castro in a working class neighborhood of Cleveland.
They escaped May 6 when Berry managed to break open part of the front door and call out to a neighbor for help.
At the trial it emerged that they were brutalized, chained up and kept in abysmal conditions.
Berry had a daughter fathered by Castro.
The white delapidated house where they were tormented for around a decade has been demolished.
Castro was sentenced to life plus 1,000 years.
At his sentencing hearing August 1, Castro had insisted he was not evil but rather addicted to sex.
"I'm not a monster. I'm sick," he pleaded.
Despite having pleaded guilty to 977 charges related to his victims' brutal decade-long ordeal, including many rapes and the murder of a foetus through beating its mother, Castro said he was not a violent man.
Castro said he had himself been sexually abused as a child and had grown up obsessed with sex, addicted to pornography and a compulsive masturbator.
He said he had not plotted the three kidnaps, but had acted on impulse.
"I am not a monster. I am a normal person. I am just sick. I have an addiction just like an alcoholic has an addiction," he said.