Police are investigating a threatening message at Maple Avenue Middle School in Littlestown.
The message was found in a bathroom Thursday morning, according to a statement on the Littlestown Area School District's website.
Students and staff were moved to the high school auditorium as a precaution while police searched the middle school with bomb sniffing dogs.
Students returned to the middle school and classes resumed when the search was completed.
According to the statement, the district will put additional security measures in place and a further update will be released at a later time.