Omar Mateen, the gunman who murdered 49 people in a gay nightclub in Orlando early Sunday morning, may have actually been gay himself and was leading a double life.

Mateen's horrifying attack on Pulse nightclub was initially thought to be a homophobic attack rooted in extremist Islamic ideology.

But now his ex-wife, a former police academy classmate and clubbers have stepped forward to say they think Mateen was gay and had been visiting Pulse since 2013.

Investigators think he could have traveled to Pulse - which was a two hour drive from his home in Fort Pierce in Southern Florida - so he wouldn't have been seen. 

It's also been revealed that Mateen used gay dating apps Grindr and Jack'd to chat to men online and was friends with draq queens at the club. 

Signs that Mateen could have been gay emerged as far back as 2006 when he asked a male classmate out on a date. 

At the time Mateen was said to be going to gay clubs and chatting up men. 

Mateen's first wife, Sitora Yusufiy, 27, whom he met online in 2009 and married soon after, told Daily News his family think he murdered the 49 because he was in turmoil about who he really was - not because he was an Islamic extremist.

'When we had gotten married, he confessed to me about his past -- that was recent at that time - and that he very much enjoyed going to clubs and the nightlife,' Yusufiy said. 

'So, I feel like it's a side of him or a part of him that he lived but probably didn't want everybody to know about.'

Yusufiy also spoke on a Brazilian TV station yesterday, joined by her fiance from the country, Marcio Dias. 

Speaking Portuguese, he told the channel that Yusufiy told him Mateen had 'gay tendencies' and had been called gay in front of her on several occasions by his father. 

He also said that she didn't believe that Mateen's supposed Islamic beliefs were at the root of his attack.

She had told the FBI that he was unstable, and that she didn't believe he was part of a terrorist group - despite him pledging allegiance to ISIS before the attack and the fundamentalists later claiming responsibility for it.

'The FBI asked her not to tell this to the American media,' he told the station.

Yusufiy has also said that Mateen 'beat her': 'After a few months he started to beat me. He was mentally unstable… he was obviously disturbed. I know he had a history of [taking] steroids. 

Yusufiy sought divorce from Mateen in 2011, after he turned violent.  

Club regulars at Pulse said they saw Mateen several times over the past three years drinking alcohol and dancing with men. 

A couple who perform as drag-queens at the popular venue in 1912 South Orange Avenue said they had seen the 29-year-old party at Pulse. 

Ty Smith and Chris Callen said the father-of-one was sometimes so drunk he had to be removed from the club.

Callen said: 'I’ve seen him a couple of times at Pulse, a couple of other people that I’ve spoken with, including an-ex security guard, have actually witnessed this guy at Pulse many times before.' 

Smith said he'd seen Mateen at Pulse 'at least a dozen times'.

'We didn't really talk to him a lot, but I remember him saying things about his dad at times,' Smith said. 'He told us he had a wife and child.' 

A security guard who worked at the club two years ago still remembered Mateen turning up to the venue, he added. 

Orlando's gay community are in shock that someone who was known to them was capable of carrying out the murderous rampage against those who seemingly had so much in common with him. 

But there were signs, even inside Pulse's safe environment for LGBT regulars, of Mateen's temper.

Callen said Mateen, who seemed like a 'nice guy' and was 'comfortable' with the draq queens, threatened someone with a knife when he became angry about a religious joke.  

A former male classmate of Mateen said the mass-murderer once asked him out on a date, according to the Palm Beach Post.

The man, who did not wish to be named, was a classmate of Mateen's in 2006, when they both attended the Indian River Community College police academy.

He said that he would hang out with Mateen alone and in groups, and that they went to gay clubs together.

He also said that Mateen had asked him out on a date at one point. 'We went to a few gay bars with him, and I was not out at the time, so I declined his offer,' he said.

He told the newspaper that he thought Mateen was gay and closeted, and that he was an 'awkward' figure.

'He just wanted to fit in and no one liked him,' he said. 'He was always socially awkward.' 

Mateen made his attack on Pulse early Sunday morning - but that wasn't the first time he'd been to the club,The Orlando Sentinel reported.  

Remarks that Mateen drank heavily conflict with his apparently strict adherence to his Muslim faith, including regular worship at a mosque in his home town of Port St. Lucie - where he was quiet and kept to himself.

And Kevin West, who was also a regular at Pulse, told the Los Angeles Times that Mateen has messaged him on gay dating app Jack'd several times in the year before the attack.

However, he said, he never actually met the man until the morning of the attack.

He saw Mateen crossing the street outside Pulse at around 1am - about an hour before the attack.

West, who was dropping off a friend at the club, recognized Mateen. 'He walked directly past me,' he said. 'I said, "Hey," and he turned and said, "Hey," and nodded his head,' West said.

West went to police as soon as he saw pictures of Mateen in news reports, handing over his phone and Jack'd login to FBI agents, who still had it as of Monday.    

The FBI are also trying to hack into Mateen's own electronic devices to find out what had happened in the days leading up to the shooting, the LA Times reported. 

Mateen married a second time after divorcing Yusufiy, to Noor Zahi Salman, with whom he had a son. 

The pair got a mortgage together in 2013, but they were living at separate addresses when he went on his rampage. 

His father, Seddique Mateen, told the Palm Beach Post that he didn't believe his son was gay. 'If he was gay, why would he do something like this?' he asked the paper.

And he had previously recounted a time when his son became angry after seeing two men kissing in Florida.

But speaking to The Canadian Press, Smith said that the story was 'bullc***'.

'That's straight-up c***,' he said in an interview at the GLBT Community Center of Central Florida. 

'He's been around us. Some of those people did a little more than (kiss) outside the bar... He was partying with the people who supposedly drove him to do this?'

Classmate Samuel King said Mateen was not homophobic when he knew him in the year after their 2004 graduation.

'What is shocking to me is that the majority of the staff at Ruby Tuesday's when I worked there were gay,' he said.

'He clearly was not anti-(gay), at least not back then. He did not show any hatred to any of us. He treated us all like the individuals we were. He always smiled and said hello.'

King, who characterized Mateen as friendly and talkative, said: 'Something must have changed.'

Courtesy Daily Mail