By Nick Gale

(CHICAGO)  More than 100 students and staff members at a South Side elementary school were hospitalized this morning after a carbon monoxide leak.

Horace Mann Elementary was evacuated around 8:30 this morning after carbon monoxide detectors went off. CPS says 104 students and seven staff members were taken to area hospitals for precautionary reasons. All were in good condition.

Students were moved to the school’s annex after the evacuation, and classes were conducted from there for the rest of the day.

Twelve of the 13 carbon monoxide detectors were just installed last month. CPS started installing them after a carbon monoxide leak at Prussing Elementary School in Jefferson Park last month sickened 71 students and seven adults.  A faulty boiler was the cause in that case.

The cause of the leak at Mann hasn’t been determined.

@ 2015 WLS News