CHICAGO (CBS) — A South Side high school was evacuated Friday afternoon, after a small explosion, Chicago Public Schools officials said.

Chicago police said Simeon Career Academy High School was being evacuated as a precaution after a small chemical explosion.

The Fire Department said a teacher and student were being taken to the hospital in good condition after suffering minor burns. But a CPS statement made no indication anyone was hurt.

“Today at Simeon High School, preparation for a chemistry lab resulted in a small chemical reaction before class began,” CPS spokesman Bill McCaffrey said. “Students were provided a safe and comfortable environment until it was safe to return to the building. An investigation is underway.”