A Brooklyn man who claimed his roommate died while drunkenly playing Russian roulette was lying about the deadly game, sources said — and was arrested Sunday for the fatal shooting.

Maciej Gorecki, 32, was charged with manslaughter and criminal possession of a weapon for fatally shooting Zdzislaw ­Golabek, 37, in the head on accident Saturday night in Sunset Park, according to law-enforcement sources.

“I can’t believe it,” said Andrzej Golabek, Zdzislaw’s brother. “He was really quiet. He never got into trouble.”

Gorecki initially told police that he was drunk and playing the deadly game when his roommate spun the cylinder and pulled the trigger on himself, the sources said.

But Gorecki changed his story, claiming that the duo had actually been drunkenly pointing the weapon at each other in their own version of the sadistic game.

Gorecki eventually admitted that there was no game — and that he had actually just pulled the trigger while aiming at his friend’s head because he thought the weapon was unloaded, the sources said.

The victim’s family gathered at his home on 45th Street and tried to make sense of the tragedy.

“We are in shock,” Golabek’s sister-in-law said. “We don’t want to talk about it.”