This past Friday around 1 pm, roughly 15 to 18 Clio elementary students became ill while at school. It's now believed that they ingested some form of a foreign substance.

The Genesee County Sheriff's Office, Clio Area Fire Department, and several ambulances responded to Edgerton Elementary School near Clio as students became sick. According to reports, the kids had symptoms of dizziness and nausea.

Obviously, the incident was extremely scary for students, teachers, and parents.

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According to ABC 12, five students went to Hurley Medical Center in Flint and four of them remained hospitalized Saturday. Several other students sought treatment at an area clinic or were released to the care of their parents at home on Friday.

Clio Area Schools Superintendent Fletcher Spears III sent a letter to out to parents over the weekend. He basically stated that the students may have may have ingested a foreign substance. What that substance was is unclear as of right now.

Authorities ruled out the possibility of a carbon monoxide or natural gas leak in the school. This makes sense because if that was the case students and teachers would have gotten sick.

Genesee County Sheriff Chris Swanson said the situation was treated as a mass casualty incident.

"We deploy all assets in a situation like this until we can triage what's going on."

The good thing is none of the illnesses appeared to be life-threatening.

The classroom was reopened for school today but not before custodians did a deep clean of the room where students got sick.

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