FRESNO, Calif. (KFSN) -- Fresno Police said the first problems began around 7 p.m. Sunday night with a shouting match inside YOLO Sushi and Karaoke Bar."The disturbance involved both males and females who were starting an argument," says Fresno Police Sgt. Todd Turney. "Eventually, that disturbance separated. Some of the group went into the establishment. Part of the other group left the location."Police say about a half an hour later, some of the group who initially left came back and another argument began. At first, it was only yelling.Police say security made the people involved leave.But they returned again 45 minutes later, and that's when officers say things got physical. Chairs were thrown along with punches. Security got the group outside and then someone pulled out a gun."I think the establishment was hit four times, I think in this exterior wall," Turney said. "There was one employee who was inside the location who was struck in the upper leg area."Investigators say the bartender will be okay, but officers say the group scattered when shots rang out.Witnesses told investigators the shooter also ran away. Officers never found the gun, but only shell casings left at the scene.The restaurant had been contracting with Fresno Police for security service but discontinued using officers earlier this year.The management company who oversees the strip mall said that although there are cameras perched outside the businesses, they don't work or record.Officers do have some leads on the shooter. They say the disturbance may be gang-related.They are still trying to track down everyone who was there Sunday night.