CHICAGO (CBS) — Police are warning Northwest Side businesses about a series of recent armed robberies.

The suspects entered the businesses with a black or silver handgun and demanded money from the victims, Chicago Police say.

The first robbery happened about 5:20 a.m. Nov. 12 in the 4300 block of North Milwaukee, police said.

The suspect was described as a 6-foot to 6-foot-2 black man between 30 and 35 years old. He wore a dark-colored hooded sweatshirt, dark-colored pants and a dark-colored skull cap.

Another robbery happened about 8:10 p.m. Nov. 14 in the 5400 block of North Harlem Avenue, police said.

The suspect was described as a 160-pound, 5-foot-8 to 5-foot-10 black man between 40 and 50 years old. He wore a brown hooded sweatshirt, black jeans and a black skull cap.

The most recent robbery happened about 8:20 p.m. Nov. 25 in the 5000 block of North Cicero, police said.

The suspect was described as a 5-foot-8 to 5-foot-10 black man between 21 and 27 years old and weighing 140 to 150 pounds. He wore a gray hooded sweatshirt, dark faded jeans and white-and-black gym shoes.

Anyone with information on the robberies should contact Area North detectives at (312) 744-8263.

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