A man accused of keeping three women captive in his run-down home and raping them over a decade had terrorised the mother of his children years earlier, beating her and locking her indoors, former relatives say.
In interviews with The Associated Press, relatives of Grimilda Figueroa, who left Ariel Castro years ago and died last year after a long illness, described Castro as a "monster" who abused her.
Castro once shoved her into a cardboard box and closed the flaps over her head, said Elida Caraballo, her sister.
"He told her, 'You stay there until I tell you to get out,"' said Caraballo, who cried as she recounted her late sister's torment.
"That's when I got scared and I ran downstairs to get my parents."
Castro, a 52-year-old former school bus driver, was arrested on Monday, when one of the three women, Amanda Berry, broke out of his house and called police while he was away. Police found the two other women inside.
The women had vanished separately between 2002 and 2004. Castro has been charged with rape and kidnapping.
He's being held on $US8 million ($A7.96 million) bail under suicide watch in jail.
During his brief arraignment on Thursday, he tried to hide his face and didn't speak or enter a plea.
Some relatives of Castro have said they were shocked by the allegations against him. An uncle, Julio Castro, said it's been difficult news to absorb.
"Of course we have taken it hard," he said. "We only knew one Ariel, my sweet nephew. He was a sweet, happy person, a musician.
"We didn't have the slightest idea of the second person in him."
Among many beatings over the years, Castro shoved Figueroa down a flight of stairs, broke her nose several times and dislocated her shoulder, Caraballo said.
Castro kept her imprisoned inside her own home, locking the doors from the inside, Caraballo said.
He forbade her from using the telephone and, after warning her not to leave, tested her to see if she obeyed, Caraballo said.
"He would go creeping downstairs, not telling her that he's home, spying on her," Caraballo said. "See who she's calling. Next thing you know, he'll pop upstairs."
Castro, to frighten his wife, kept a mannequin wearing a dark wig propped up against a wall, and once when she was returning home with her arms full of groceries he jumped into the doorway with it, frightening her so badly she fell and hit her head, Caraballo said.
In 1996, Castro hit Figueroa for the last time, family members said.
Figueroa ran outside with one of her sons, crying out to neighbours, just as the captive women did on Monday, Caraballo said.
"The neighbours went across the street to get her," Caraballo said. "And that was the last time she ever stepped in the house."
