Thirteen students from a Chicago high school were hospitalized on Tuesday after eating gummy bears that were apparently laced with an unknown substance.

It is unclear whether the teenagers from Naperville North High School knowingly took laced gummies, but some students told police the substance was marijuana. That allegation has not been confirmed, CBS reports.

While 11 of the students were listed as being in stable condition, two were released from the hospital. Reported symptoms include dizziness, rapid heart rate and dry mouth. A 17-year-old was taken into custody for questioning.

“Each student had varying degrees of discomfort and subsequent treatment,” school officials said. “We continue to review the specifics of the situation and will address it appropriately.”

[CBS]

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