Police said at least four robberies have happened in the Woodlawn neighborhood's 6600-block of South Blackstone Avenue.
The most recent crime happened on Monday morning around 11:40 a.m. Another robbery happened on Saturday around 3 p.m.
The two other robberies happened on Feb. 12 around 12:30 a.m. and on Feb. 5 around 12:50 p.m.
The victims met the suspect on a dating app and agreed to meet in person, police said. In each incident, when the suspect arrived, he took out a gun and demanded the victim's property. Each time, the victim complied and handed their belongings over.
The suspect is described as a man around 22 years old who is about 6-foot-1 and weighs 165 to 190 pounds. He was seen wearing a black jacket and black pants.
Area One detectives asked anyone with information to call them at 312-747-8380 or submit an anonymous tip at CPDTIP.com and use reference #P26-1-017A.
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