Fire officials said emergency crews responded to a scene near Kostner and Monroe around 8:30 p.m.
CPD said about 15 minutes earlier, at 8:15 p.m., the four victims were near the street in the 4100-block of West Monrose when they were approached by an unknown vehicle. Someone inside the car opened fire at them, striking all four.
Police said an 11-year-old boy was struck in the thigh and taken to Stroger Hospital. A 31-year-old woman was struck in the arm and taken to Rush University Medical Center. A 33-year-old man was struck in the back and taken to Stroger Hospital. And a 48-year-old man was also struck in the back and taken to Stroger Hospital.
All four were initially reported to be in serious condition, police said.
No one is currently in custody. An investigation by Chicago police is ongoing.