Tuscola, IL- Even more children stayed home today after a mystery illness swept through a Tuscola Elementary School. 

Some parents of sick students at North Ward Elementary believe something their kids ate or drank at school caused the illness.

But there is no official word on what caused the illness.

The Douglas County Health Department has launched an investigation and have not ruled out food poisoning as a possible cause. Symptoms have included vomiting, diarrhea, abdominal pain.

Storm Center 17 talked to Superintendent James Voyles, who said he does not think it's necessary to close the school. For now, Voyles believes cleaning and disinfecting while class is in session is the best medicine.

Voyles says only children at North Ward Elementary have been affected.

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