Updated 03/17/11 – 3:42 p.m.

BLUE ISLAND, Ill. (CBS) —Thirty people were taken to hospitals Thursday afternoon after they got sick when chemical fumes spread through a south suburban middle school.

A hazardous materials alarm was called at Paul Revere Intermediate School at 12331 Gregory St. in Blue Island around noon Thursday.

Blue Island Mayor Don Peloquin told WBBM Newsradio 780’s Steve Miller that chemicals were accidentally mixed in a utility closet at the school, making people sick when the smell made its way through the ventilation system.

“We know there was some bleach. We know there was some Drano, or drain cleaner,” Peloquin said.

LISTEN: Newsradio 780’s Steve Miller reports

Peloquin said 30 people were taken to hospitals because of the smell; 22 students and 8 children.

“It’s a very strong bleach odor. I’m outside where it’s dispersing. I’m not exactly sure how strong it is inside the building,” he said.

One building at the school was evacuated as a result. Fire department crews secured the scene by 1:10 p.m.

All students who weren’t taken to hospitals were moved to Paul Revere Primary School and parents were advised to pick students up at Hart Park in Blue Island after school, according to a statement on the Cook County School District 130 website.

Peloquin said Paul Revere Intermediate School would be closed Friday, so the building could be aired out and the spill could be cleaned up.

Parents with questions should call 708-489-3533 with any questions.

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