The boy has been charged with aggravated battery and unlawful use of a weapon in the shooting, police said.
CPD said the boy was arrested Monday in Chicago, after being identified as the person who shot the girl in the 2200-block of South Sawyer Avenue on Sept. 7.
The girl was hit in the back, police said.
She was taken to Mt. Sinai Hospital in serious condition.
The suspect is due in court Tuesday.
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