NEW YORK (CBSNewYork/AP) — The ex-wife of the gunman behind the massacre at an Orlando nightclub revealed that he repeatedly beat her while they were married.

Sitora Yusufiy is the ex-wife of Omar Mateen, who was identified as the gunman who killed 50 people at the gay nightclub Pulse. She told The Washington Post that the marriage was normal at first before he became abusive.

“He was not a stable person,” she said. “He would just come home and start beating me up because the laundry wasn’t finished or something like that.”

Yusufiy described her ex-husband’s behavior to reporters late Sunday night.

“He was mentally unstable and mentally ill. That’s the only explanation that I can give. And he was obviously disturbed,” she said.

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Yusufiy said she met Mateen online about eight years ago and decided to move to Florida and marry him.

They were together for only a few months and her parents intervened when they learned Mateen had assaulted her. She said he wasn’t very religious and gave no signs of radical Islam. She said he owned a small-caliber handgun and worked as a guard at a nearby facility for juvenile delinquents.

“He seemed like a normal human being,” she told The Washington Post, adding that Mateen “was a very private person.”

Yusufiy’s father told CBS News from his Edison, New Jersey, home said they called the cops when they learned she was being abused by Mateen.

“The met online, and all of a sudden they decided to marry, and then she went there for four months, and then actually what happened was she was abused by him, and then we went and picked her up from there,” he said. “We even called the cops to pick up her belongings.”

The man said he was surprised at what Mateen did.

“I was really shocked. Why would he do such a thing, so many people?” he said.

Mateen, 29, was from Port St. Lucie, Florida, but was born in New York to Afghan parents.

CBS News reported that Mateen called 911 and pledged allegiance to the Islamic State of Iraq and Syria prior to the shooting. ISIS has claimed responsibility for the massacre.

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