CHICAGO (STMW) — Police are warning residents of a series of armed robberies over the past week in the West Ridge neighborhood on the Northwest Side.

The robberies occurred:

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• at 4:05 p.m. Jan. 12 in the 6900 block of North Washtenaw Avenue;
• at 8:10 p.m. Jan. 13 in the 6600 block of North Maplewood Avenue; and
• at 8:52 a.m. Jan. 16 in the 7000 block of North Washtenaw Avenue.

The robber approached people from behind and pointed a gun at the victims’ heads while demanding they give everything they have, according to a community alert from Chicago Police. The suspect took a purse, cell phones, and money.

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In one incident, the suspect is described as a 38-year-old black man standing 6-foot and wearing a black jacket, back jeans and yellow gym shoes, police said. In another incident, the suspect is described as a black man, between 20 and 30 years old, standing 5-foot-7, weighing 200 pounds with a light complexion. He wore glasses and a black jacket. The suspect was also described as a black man standing 6-foot-1 and wearing black frame glasses, a red knit ski cap and light gray sweatpants, police said.

Anyone with information about the robberies is asked to contact Area North detectives at (312) 744-8263.

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(Source: Sun-Times Media Wire © Chicago Sun-Times 2016. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)