In each incident, three males approach victims on foot, display a black handgun and take the victim's personal property or vehicle before fleeing the scene, Chicago police said in a community alert.
The robberies happened:
- About 2:55 a.m. July 27 in the 5100 block of South Kimbark Avenue;
- About 9:30 p.m. July 29 in the 5400 block of South Woodlawn Avenue;
- About 7:15 p.m. July 31 in the 5200 block of South Kimbark Avenue;
- About 7:25 p.m. Aug. 2 in the 1400 block of East Hyde Park Boulevard.
Anyone with information is asked to contact Area One detectives at (312) 747-8380.