An off-duty police officer working a high school security detail chased down and shot a student Tuesday after the teen set off a campus metal detector then fled during a search, a Chicago Public Schools spokesman said.

The boy, a 16-year-old Phillips High School student who was suspended from school at the time, was in stable  condition at an undisclosed hospital Wednesday.

Chicago Public Schools spokesman Michael Vaughn said the boy went through the school's metal detectors at about 8:30 a.m. Tuesday, setting off the alarm. The school is at 244 E. Pershing.

Vaughn said that the security guard and a Chicago police officer who was working security at the school began chasing the student.

The officer shot the teen near a CTA elevated train station in the 300 block of East 43rd Street. According to Vaughn, a  gun was recovered from the scene.

Police officials confirmed the incident but directed all questions to the Independent Police Review Authority. The IPRA's chief administrator Ilana B.R. Rosenzweig could not be reached for comment Wednesday.

Vaughn said he did not know why the boy had been suspended.