COSTA MESA (CBSLA.com) —  Several students at an Orange County middle school were sickened Wednesday after eating pot brownies.

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Firefighters were sent to TeWinkle Intermediate School on California Avenue in Costa Mesa around 12:45 p.m.

Newport-Mesa Unified School District officials said five seventh-graders went to the school’s nurse and complained of stomach aches.

Other classmates confessed those students ingested brownies laced with marijuana, according to Sky9’s Gil Leyvas.

Three children were transported to Hoag Memorial Hospital Presbyterian in Newport Beach as a precaution.

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Their conditions are unknown.

Two other kids went home with their parents.

Costa Mesa police later arrested a 12-year-old male student who allegedly brought the brownie to school. He was booked for contributing to the delinquency of a minor.

Last month, seven kids at Pomona Elementary School in Costa Mesa shared a pot brownie after a 12-year-old boy brought the treat to the campus.

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The investigation is ongoing.