My Palm Beach Post – A licensed security guard who held a firearms license, Mateen started working for G4S in 2007, according to a company newsletter. While there, he had been a screener at an area courthouse, said Daniel Gilroy, a co-worker.

Gilroy worked with Mateen after he transferred to a security guard detail at PGA Village in Port St Lucie.

Mateen took his prayer mat to work and prayed regularly, but, Gilroy found Mateen’s attitudes toward and comments to gays, African-Americans and women crude.

And then there was the screaming. Mateen was constantly agitated and on the verge of an outburst, said Gilroy, who could hear his rants even outside of the guard house.

Fed up, he told Mateen he wasn’t interested in being friends.

That’s when he went “boiled-rabbit crazy,” said Gilroy, with Mateen texting him, pleading for a reconciliation of friendship, and accusing him of betrayal so frequently that Gilroy’s girlfriend believed the two men might have been having an affair.

Rather than continue, Gilroy quit his job.

Mateen’s former wife was also on the receiving end of his outbursts.

Speaking to the press Sunday night, she described violent outbursts and beatings.”My family literally had to rescue me,” she said.

Greg Davis, a St. Lucie County man, said a friend who worked with Mateen “told me (Mateen’s) demeanor recently had drastically changed. He was working out, he really bulked up. He showed up with a rental van the last night he was at work. That’s strange because he loved his car, ” said Davis.

None of the erratic behavior showed up in the mosque, or was obvious to his neighbors.

“I would wave and say hello,” said Esmerelda Gonzalez, whose parents live next door to Mateen’s former home on

Bayshore Boulevard. “We never talked beyond that. He came over and bought stuff at a yard sale we had. He came over once and asked if he could use our property for parking because he was having a family gathering.”

Visitors sometimes came to the house at odd hours, sometimes as early as 4 a.m., said Gonzalez, but she thought nothing of it.

At the mosque, Rahman said he can’t remember ever having a conversation with Mateen.

Mateen, he said, attended “sporadically” — frequently with his toddler son in tow — but his three sisters were regular faces, sometimes performing chores and cleaning the mosque.

If Mateen leaned toward an extremist version of Islam, he kept it from his imam, who wept as he began Sunday evening prayers at the mosque.

“There is nothing outside the door that says you can’t come in and worship God and be here and pray if you are gay,” Rahman said. And Rahman said he speaks out against terrorist groups at every gathering.

“They have hijacked our religion,” Rahman said. “They have caused more trouble for us than anything.”