Childhood Friend and Ex-Wife Talk About Omar Mateen.  Click here for more trending videos.

Orlando nightclub shooter's ex-wife 'worried about her safety' while married

The ex-wife of the man authorities said killed at least 50 people at an Orlando, Florida, nightclub spoke at a news conference Sunday night.

>> Read more Orlando nightclub shooting stories

"To be in some way affiliated, at on​e point in my life, to somebody that causes such a tragedy -- it shook me," Sitora Yusufiy said at the news conference in Colorado.

Police said 29-year-old Omar Mateen, an American, opened fire at Pulse nightclub Sunday morning, killing at least 50 people and injuring 53. He was later killed in a shootout with a SWAT team, authorities said.

Yusufiy told The Washington Post that she met Mateen online about eight years ago and decided to move to Florida and marry him. Yusufiy said at first the marriage was normal, but then he became abusive.

"That's when I started worrying about my safety," Yusufiy said.

According to The Associated Press, Yusufiy said Mateen beat her repeatedly while they were married.

"He was mentally unstable, mentally ill," Yusufiy said.

They were together for only a few months and her parents intervened when they learned Mateen had assaulted her. She sid he wasn't very religious and gave no signs of radical Islam.

"He would get in his tempers and express hate towards everything," Yusufiy said.

Yusufiy said he owned a small-caliber handgun and worked as a guard at a nearby facility for juvenile delinquents.

Yusufiy said his family was from Afghanistan, but her ex-husband was born in New York. His family later moved to Florida.

Support real journalism. Support local journalism. Subscribe to The Atlanta Journal-Constitution today. See offers.

Your subscription to the Atlanta Journal-Constitution funds in-depth reporting and investigations that keep you informed. Thank you for supporting real journalism.

The Associated Press contributed to this story.