White said the alleged shooter was part of a group of individuals who had been told to leave the club earlier in the evening following an incident.
The group allegedly returned at closing armed with a gun, and one of the individuals started shooting either in the air or at the crowd of patrons outside, White said.
He said the victim didn't know the suspects and appeared to been hit at random.
The suspects then fled in a silver sedan. A witness, however, was able to capture a partial plate number, which led officers to a residence in Cottonwood Heights.
Four people were detained for questioning, and one of those men was later arrested on suspicion of aggravated assault, White said.