OHIO, (CNN) — Seven middle school students will face charges for allegedly putting bodily fluids in food that was served to teachers.

The incident happened in May during a cooking contest.

Prosecutors say the suspects are all 14-year-old boys.

They’re accused of putting semen on crepes and urine in barbecue sauce they prepared for class.

The teachers ate the food without knowing what happened.

Assault charges were filed on Tuesday.

An attorney representing four of the students said the incident was a prank.

The eight-graders will face a judge in the coming weeks