The shooting took place at about 10:42 p.m. in the 7500-block of South Stony Island Avenue.
Police said two men, ages 25 and 23, were in a silver sedan stopped at a red light when a red van pulled alongside and someone inside fired shots at them and fled.
The 23-year-old man was wounded in the chest and neck and transported to the University of Chicago Medical Center in critical condition, police said.
The 25-year-old man was shot in the leg and transported to the University of Chicago Medical Center in critical condition, police said.
A 46-year-old woman driving an SUV was also stopped at the stoplight and wounded in the right arm, police said. She was listed in fair condition at Jackson Park Hospital.
No one is in custody and Area Two detectives are investigating.
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