CHICAGO (CBS) — Police on Sunday warned the public about two incidents in Bronzeville, in which the victims got robbed and carjacked after arranging to meet a person who was supposed to be buying something from them.

In the two incidents, the victims arranged to meet with someone to sell them an item they had agreed to buy on an online marketplace platform, police said.

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Instead, each victim was forced into his own car at gunpoint by four men, who went on to physically attack him and take his personal property. The attackers then forced each victim to go to ATM to give them money, before finally driving away in his car.

The robberies happened at the following times and locations:

• At 3 p.m. Friday, June 25, in the 3500 block of South Cottage Grove Avenue;

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• At 12:15 p.m. Saturday, July 17, in the 500 block of East 33rd Place.

The attackers are believed to be between 16 and 24 years old, police said.

The public is reminded to check a seller or buyer’s online profile before meeting them in person, and always to meet at a public place such as a police station when making such a transaction.

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Anyone with information about these robberies is asked to call Area One detectives at (312) 747-8384.

CBS 2 Chicago Staff