By CBS 2 Chicago Staff

CHICAGO (CBS)–Police are asking for help catching a group of men who have stolen designer purses from at least four stores on or near the Magnificent Mile in the past week, including an incident when they seriously injured an elderly security guard.

Chicago police said four times in the last week, a group of at least four men have gone into a store, grabbed purses off the displays and taken off in getaway car.

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All of these thefts took place in the afternoon.

Recent incidents took place at the follow locations:

• 900 block of North Rush St., Sunday, August 15

• 0-100 block of East Huron St., Monday, August 16

• 900 block of North Michigan Ave., Monday, August 16

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• 600 block of North Michigan Ave., Saturday, August 21

Police have security footage of the robberies.

CPD Chief of Detectives Brendan Deenihan said, during the robbery at 900 N. Michigan Ave., the thieves knocked down an elderly security guard while stealing $43,000 worth of purses.

The security guard suffered a fractured skull and bleeding on his brain, and remains in “extremely serious condition” in the intensive care unit, according to Deenihan.

Police did not have detailed descriptions of the robbers, who were wearing masks and hoodies.

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Anyone with any information is asked to call Area Three detectives at (312) 744-8263.

CBS 2 Chicago Staff