Chicago police said the shooting happened as officers were trying to disperse a large gathering in the 5300-block of South Princeton Avenue just after midnight.
Officers said they tried to stop a man who they believed had a gun.
During a struggle, police say that gun went off, shooting the man in the leg.
Officers did not fire their weapons, according to Chicago police.
The man is expected to recover and is in police custody.
No other injuries were reported.
No other information regarding the large gathering was available.
About three hours later, a man was shot to death in the 4800-block of South Princeton Avenue, police said. A woman was also shot around the same time.
CPD did not connect the shootings with the large gathering.
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