It happened around 2 a.m. Sunday morning.
Police say a security guard shot a 30-year-old man at the LB's Lounge on the 5400 block of North 5th Street.
According to investigators, it happened after the guard asked the man to leave. The man left, but then returned and threatened the security guard with a gun.
That's when the security guard fired his gun, striking the man in the shoulder.
The man was taken to the hospital, where he is in stable condition.
Officers recovered his gun and are taking him into police custody.
The security guard is cooperating with police. Officials say this is an ongoing investigation.