Hickory Career & Arts Magnet School in North Carolina was evacuated on Tuesday after multiple students and a teacher got sick.
Eight students and one teacher were taken to the hospital.
Officials at first believed there might have been a carbon monoxide leak, but are now unsure what caused the issues, reported the Hickory Record.
Dance instructor Jan Roundy was the teacher who got sick.
Four students were taken to Frye Regional Hospital.
Four other students were taken to Catawba Valley Medical Center.
More students are sick and officials are waiting for parental approval before taking them to a hospital.
No one is in life-threatening condition.
A reporter with the Record saw a student vomiting.
Story developing; check back for updates
