During the robberies, two men confront victims, flash a handgun and mug the victim, according to the alert.
A person was robbed about 12:20 p.m. Sunday in the 2300 block of West 61st Street. Another was robbed about 12:35 p.m. Monday in the 5900 block of South Artesian Avenue, police said.
The armed robbers are described as black males between the ages of 18 and 21, standing 5-foot-10 and weighing between 160 and 165 pounds.
Police ask anyone with information to call 312-747-8380.