NEW ROCHELLE - Toxic fumes closed a school for kids with special needs in New Rochelle today.

School officials say fumes from a recently installed heating unit set off alarms at the Hallen School on Centre Avenue.

High levels of carbon monoxide in the building caused officials to dismiss the students as a precaution. Carbon monoxide is an odorless, but toxic, gas that can kill if undetected. "It was giving off some low levels of CO. We had companies respond and take levels with our gas meters. It turned out we had some elevated readings in the gym. So what we did was ventilate, and call Con Edison," says fire Capt. Donald Bradley. Bradley says levels dropped quickly at the school after ventilation.

No injuries have been reported.