Three males were standing in the 9200-block of South Halstead Street in the city's Brainerd neighborhood just before 5:45 p.m. when an unknown vehicle pulled up and someone inside began firing at the group, according to Chicago police.
A 16-year-old was shot in the back and transported to Christ Hospital in critical condition, police said.
A 20-year-old man was shot in the leg and transported to a nearby hospital, and a third person of unknown age was grazed by a bullet but declined medical attention, police said.
No one is in custody and Area Two Detectives are investigating.