CHICAGO (CBS) — A 15-year-old girl was charged with reckless conduct after she allegedly sprayed Mace inside a Bronzeville school on the South Side, injuring 20 people.

About 11:30 a.m., the student pulled out Mace and sprayed it inside a classroom at Chicago Military Academy, 3519 S. Giles Ave., said Fire Media Affairs spokesman Joe Roccasalva.

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Nineteen students and one adult inside the classroom were transported to area hospitals, including University of Illinois Medical Center at Chicago, University of Chicago Medical Center, Saint Bernard Hospital and Health Care Center, John H. Stroger, Jr. Hospital of Cook County and Mercy Hospital and Medical Center, Roccasalva said. All of them are in good condition, he said.

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The 15-year-old girl who sprayed the Mace was charged with reckless conduct, police said. Her name was not released because she is a juvenile.

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“School officials were alerted to an accident involving Mace at Chicago Military Academy this afternoon and took appropriate actions to ensure that students were safe,” CPS spokesman Joel Hood said in an email Monday afternoon.