Firefighters from multiple agencies were called to a three-alarm fire t Proviso East High School in Maywood Saturday night.
The fire was reported at about 9 p.m. at the high school, 807 South First Avenue, and was quickly elevated to a three-alarm fire at about 9:40 p.m., officials said.
No one was injured.
About thirty people watching a theater performance in the auditorium were evacuated.
Firefighters were able to contact the fire to one classroom but smoke filled most of the second level of the building.