Reports are emerging that the shooter who killed 49 in an Orlando gay nightclub frequented the club and may have used gay dating apps.

One man told the Canadian Press that Omar Mateen had been frequenting Pulse, the club where he opened fire early Sunday, for years.

"It's the same guy," Chris Callen told the Canadian Press, who performs under the name Kristina McLaughlin. "He's been going to this bar for at least three years."

Mateen's father told media that his son was outraged by the sight of two men kissing.

But the Orlando Sentinel reported that Mateen was spotted inside the club a dozen times.

"Sometimes he would go over in the corner and sit and drink by himself, and other times he would get so drunk he was loud and belligerent," Ty Smith told the Sentinel. 

The Los Angeles Times reported that another man was in contact with Mateen for more than a year on the gay hookup app Jack'd.