The shooting happened at about 9:17 p.m. in the 800-block of N. Dearborn Street, police said.
A 34-year-old man and a 37-year-old man were involved in an argument when someone pulled out a gun.
The 34-year-old was shot in abdomen. He was taken to Northwestern Hospital in critical condition.
The 37-year-old was shot multiple times about the body. He was also taken to Northwestern Hospital in critical condition.
CPD said a person of interest is in custody, and charges are pending.
A weapon was found at the scene.
No other information was available.
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