The crash occurred at about 4:12 a.m. in the 5700-block of West Grand Avenue.
Police said a 24-year-old man was walking in the crosswalk when a white Ford F-150 traveling westbound hit the man.
The vehicle then fled in an unknown direction, police said.
The victim was transported to Loyola Hospital, where he was in serious condition.
No one is in custody. Area Five detectives are investigating
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