The recent crimes happened on the South Side.
In each robbery, two to three male suspects robbed the victims after messaging each victim through a dating app and arranging for them to meet at a specific address.
In two robberies, the suspects had the victims meet them at an abandoned building in the 800-block of East 90th Street in Burnside. In the first incident on Sept. 15, the suspects used a knife and stole a handgun from a victim. In the second incident on Sept. 24, the suspects used a handgun.
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Another similar robbery happened last Thursday in the 8100-block of South Marshfield Avenue in Auburn Gresham, where the suspects again used a handgun, police said.
Since then, at least two more robberies have occurred at 11:45 p.m. Monday in the 8100-block of South Marshfield Avenue and just before 9 p.m. Wednesday, in the 1600-block of West 82nd Street.
The suspects have demanded money from relatives via cash apps and even stole a victim's vehicle, police said.
Chicago police continue to investigate.
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