Two incidents happened on Sunday, Dec. 28, police said.
In each incident, police said the suspect followed the women into a garage and used physical force to take their items.
The suspect ran off with the victims' cell phone, Ventra card, cash, purse and shopping bags, police said.
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The suspect was wearing black clothing and a black balaclava-style mask, police said.
Chicago police said the incidents happened at the following locations:
-8100-block of West Addison Street at 1:14 p.m.
-3200-block of North Newland Avenue at 2:49 p.m.
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