NAPLES (NEWS CENTER Maine) -- New protocols are in the works to keep track of bathroom visits after a bomb threat shut down Lake Region Middle School in Naples.

Visitors to the MSAD 61 website were greeted by a message advising that classes are canceled for Tuesday. All other schools in the district are running normally. While middle school students stayed home, their teachers still reported to work at the high school.

Staff at the superintendent's office said the closure was prompted by a threatening message found Monday afternoon on the wall of a boy's bathroom. The message claimed a student planned to bring a bomb to school.

In addition to closing the school for the protection of students, district staff also notified police. But staff said they have every expectation that classes will resume on Wednesday.

To prevent further disruptions, administrators said the school will institute a stricter sign-in policy for students to use the bathrooms.