The man was on the street in the 6000-block of West Waveland Avenue in Portage Park about 10:15 a.m., when four suspects exited a nearby vehicle and approached him, CPD said.
They began going through his pockets and demanding his property, police said.
One of the suspects hit him in the head with a gun, according to police.
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The suspects fled south on Austin Avenue, and the victim was taken to Illinois Masonic Hospital in good condition, CPD said.
Eventually, the suspects' car crashed in the 3900-block of West West End Avenue in East Garfield Park.
Area Five detectives are investigating.
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