A review is underway after Ariel Castro was found hanged in his Ohio prison cell late on Tuesday, officials said.
Castro had been incarcerated since August 5 at the Correctional Reception Center, a prison processing facility outside Columbus, the state capital, about 150 miles southeast of Cleveland.
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.
A thorough review of this incident is underway.
More top news
Donald Trump made a number of "Day One" promises during the US election campaign. So what were they?
The white sheepdog puppies were pulled out by rescuer workers after surviving five days under tons of snow and rubble.
The Defence Secretary Michael Fallon repeatedly refused to confirm details of the test when he was summoned to the Commons.