Police said the man demanded money from cashiers in the 4300 block of North Kedzie Avenue and the 3100 block of West Irving Park in the Albany Park neighborhood.
The robberies happened on Feb. 4 between 7 p.m. and 7:30 p.m.
The man is described as around 6 feet tall with a small build, police said. He wore a black hooded sweatshirt and jeans.
Police asked anyone with information to call them at 312-746-7394.
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