Police said the shooting happened in the Englewood neighborhood's 6300 block of South Stewart Avenue just before 11:30 a.m.
A 14-year-old boy was standing outside when someone approached him before taking out a gun and opening fire, police said.
Police said the victim, shot in his upper chest, was transported to Comer Children's Hospital in critical condition.
The gunman, described only as male, is not in custody, police said. Area One detectives are investigating.
Police did not immediately provide further information about the shooting.
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