Police said the shooting happened in the West Garfield Park neighborhood's 4600-block of West Monroe Street just after 1:30 a.m.
Officers responded to a call about a person shot and found a 25-year-old man who had suffered a gunshot wound to his back. He was pronounced dead on the scene.
Police said a 34-year-old man was also struck by gunfire. He was taken to Mount Sinai Hospital, where he is listed in critical condition.
Further investigation revealed that an unidentified male suspect shot the victims before fleeing the scene on foot, police said.
There is no one in custody and Area Four detectives are investigating.
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