The robberies happened within blocks of each other on South King Drive.
Police are warning residents about a string of armed robberies reported this month in Washington Park and Parkway Gardens on the South Side.
In each incident, at least one man approached someone, brandished a handgun and demanded property, according to a community alert from Chicago police.
All robberies took place on South King Drive, police said. One happened about 4:46 p.m. May 8 in the 6200 block and another about 3:30 a.m. the next day in the 6500 block.
Three more incidents took place during the morning hours of May 13, May 22 and May 23 between the 6300 and 6500 blocks.
The suspects are described as men between 15 to 25 years old, standing 5-foot-6 to 6 feet tall and weighing 150-220 pounds.
Anyone with information should call Area Central detectives at 312-747-8380.