The first took place about 1:20 a.m. in the 600-block of West Van Buren Street in the West Loop.
CPD said a 28-year-old man was leaving a business on the block, when a white sedan with four suspects inside pulled up next to him.
One suspect pulled out a gun and demanded the victim's belongings, CPD said.
The man complied and the suspects drove west on Van Buren, police said.
SEE ALSO: Suspect jumps into fleeing armed robbery victim's car in the Loop, fires gunshot: police
About 90 minutes later, a 26-year-old man was outside in the 400-block of North LaSalle Drive in River North, when four suspects approached.
The suspects kicked the victim and implied a weapon before demanding his belongings, police said.
The victim complied and the suspects got into a silver sedan and drove north.
No injuries were reported and Area Three detectives are investigating.
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