The shooting took place at about 12:44 a.m. in the 5000-block of West Justine Street.
Police said the victims were in a parked vehicle when a dark-colored sedan pulled up.
Two male suspects got out of the sedan and fired shots before fleeing in the sedan, police said.
The 19-year-old man was pronounced dead at the scene and the 20-year-old victim was transported to the University of Chicago Medical Center, where he was later pronounced dead police said.
Area One detectives are investigating.
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