THOMSON, Ill. — Tear gas drifting from a northern Illinois prison disrupted a middle school field trip to a farm, causing symptoms in about 30 seventh graders and school staff.

Authorities say the tear gas was being used during a training exercise Thursday at the federal penitentiary in Thomson, about 130 miles west of Chicago near the Iowa border.

West Carroll School District Superintendent Adam Brumbaugh said Friday that prison officials, local emergency crews and police made sure students were evaluated and treated.

The students were gathering potatoes in a field near the facility when their eyes and skin became irritated. Some had trouble breathing.

About two dozen students from West Carroll Middle School were treated at a nearby hospital.

Brumbaugh says families will receive follow-up information.

VIAThe Associated Press
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