New Haven police arrested a man at Red's Café, at 320 Ashmun Street, just before 12:30 a.m. on Sunday after receiving a report of someone inside with a gun, police said.
A bar employee told police she'd argued with Sean Peterson, 38, of New Haven, when he insisted on entering the bar on ladies night, police said.
She told police that Peterson displayed a gun when she told him he couldn't enter the bar because he wasn't a lady, police said.
After Peterson went to the bar, the employee and the owner called police.
When police responded and approached Peterson, he reached into his pocket, swore at the officers and fled, police said.
Officers tackled Peterson after what they called a violent struggle and removed a knife from his left pants pocket and a .41 caliber Smith & Wesson model 657 Magnum revolver, police said.
Police said they also confiscated a black ski mask.
Peterson was charged with criminal possession of a revolver, possession of the revolver without a permit, threatening in the second degree and interfering with police.
He was also served with an outstanding warrant