The crash occurred in the 100-block of North DuSable Lake Shore Drive at about 4:20 a.m., police said.
A Mazda 6 sedan was traveling northbound in the southbound lanes when it hit a Chevy sedan, police said.
The driver of the Mazda fled on foot, police said.
A 26-year-old man driving the Chevy suffered fractures and abrasions and was transported to Northwestern Memorial Hospital in serious condition, police said.
No other injuries were reported and detectives are investigating.
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