WAUSAU — A written threat discovered inside a local middle school that prompted increased security throughout the day was a prank, according to the Wausau Police Department.

The message was found Tuesday in the large group room at Horace Mann Middle School, police said. An email was issued to staff and parents alerting them to the potential threat, and a school resource officer was at the school throughout the day to ensure student safety.

Later, investigators identified a student as having made the note and confirmed it was a prank, police said in a statement.

“We join the Wausau School District in asking parents to remind children that making threats, even in a joking manner, is not appropriate and will be taken seriously, regardless of one’s intent,” a Wausau Police Department news release reads. “We can help by encouraging our children to be active members of their school community, and report suspicious activity or comments to a trusted adult at school.”