OWATONNA, Minn. (AP) - Owatonna High School had to be evacuated after fire broke out in the school's auditorium.

The fire started in the auditorium curtains around 12:30 p.m. Wednesday. Sprinklers went off and contained the fire, which was quickly extinguished by firefighters.

Owatonna Fire Chief Mike Johnson says no one was hurt. Fire and water damage was limited to the stage and auditorium, but part of the school's lower level had smoke damage.

All the students were safely evacuated. Officials decided to cancel the school day shortly after the evacuation. Authorities don't know what caused the fire. The State Fire Marshal's office will help investigate.

Superintendent Peter Grant says classes will begin on time Thursday.