SAN JOSE (CBS SF) — Students at a Bay Area high school were sickened following some kind of chemical exposure on campus Wednesday, with six requiring hospitalization.

The incident happened at Oak Grove High School in San Jose just before 3 p.m. Wednesday.

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San Jose Fire Department spokesman Capt. Mitch Matlow said a total 12 people experienced symptoms described as burning in their noses and mouths in a classroom at the school.

All were decontaminated and treated at the school, whild six were taken to a hospital.

A hazardous materials crew in protective gear was in the school trying to determine what the substance was that caused the respiratory distress.

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Fire officials urged others who were in the classroom but who have gone home to shower and wash their clothes to call 911 if they feel sick.

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