Police said officers responded to the River North neighborhood's 500-block of North Franklin Street around 3:15 a.m.
A man around 25 years old was arguing with someone on the sidewalk when that person, a male of an unknown age, took out a gun and fired several shots, police said.
Police said the victim, shot in the chest multiple times, was taken in critical condition to Northwestern Hospital, where he was later pronounced dead.
The shooter fled the scene.
There is no one in custody, and Area Three detectives are investigating.
Police did not immediately provide further information about the shooting.
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