Police said a group of suspects approached a Hyundai sedan containing two men, 38 and 22, in the Logan Square neighborhood's 3700-block of West Armitage Avenue just after 11 p.m.
The group began to damage the sedan, according to police, and an altercation ensued.
At one point, one of the suspects took out a sharp object and stabbed the 38-year-old man in the back before fleeing the scene, police said.
The 38-year-old was transported to Stroger Hospital, where he is listed in fair condition.
The 22-year-old declined medical attention.
Area detectives are investigating. Police did not immediately provide additional information.
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