A man with a knife robbed a business in the 3100 block of North Milwaukee Avenue, police said.

CHICAGO — A man with a knife has held up three businesses around the city since the end of August.

During the robberies, the man went into a business and grabbed merchandise, according to a Chicago Police business alert. The man then went up to the cashier while holding a knife and demanded money.

The robberies happened at:

• 9:50 p.m. Aug. 21 in the 5000 block of West North Avenue
• 7:28 a.m. Aug. 24 in the 6300 block of North Nagle Avenue
• 2:53 a.m. Thursday in the 3100 block of North Milwaukee Avenue

The robber is described as a white man who is 40-60 years old, 150-200 pounds and 5-foot-4 to 5-foot-8, police said.

Anyone with information about the robberies was asked to call police at 312-744-8263.

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