The father of the shooter who killed 50 people at a gay nightclub in Florida said his son became enraged recently when he saw two men kissing — and that may have been what sparked the worst mass shooting in US history.

Mir Seddique, shooter Omar Seddique Mateen’s father, insisted to NBC News that the slaughter at Pulse in Orlando “has nothing to do with religion.”

“We were in Downtown Miami, Bayside, people were playing music. And he saw two men kissing each other in front of his wife and kid and he got very angry,” Seddique told the network.

“They were kissing each other and touching each other and he said, ‘Look at that. In front of my son they are doing that.’ And then we were in the men’s bathroom and men were kissing each other,” he continued.

Mateen, 29, was a U.S. citizen with no apparent criminal history, was born to Afghan parents in 1986 and was living in Port St. Lucie, according to multiple media reports.

Authorities are probing the rampage as an act of terrorism.

“At this point, this is an incident, as I can see it, we can certainly classify as a domestic terror incident,” Jerry Demings of the Orange County Sheriff’s Office said.