ROSWELL, Ga. -- Eighteen people were treated for breathing problems Wednesday after a chemical spill at a suburban Atlanta high school, an official said.

A student, a police officer and two teachers were taken to a hospital after a pint of formaldehyde spilled in a bathroom at Centennial High School, said Paul Piccirilli, assistant chief of the Roswell Fire Department. Fourteen other people were treated at the scene, he said.

Classes were dismissed for the day, Piccirilli said.

Officials spent the afternoon airing out the school, which has more than 2,000 students. There was no word on what caused the spill.

Special needs students were transferred to Hillside Elementary School.

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