Notre Dame Academy in Green Bay is on a “level two” lockdown, WBAY reports.
Nearby Franklin Middle School is also on lockdown as a precaution. Classes are continuing at both schools.
The lockdowns come after an unspecified threat was received via email from someone who is not a student at Notre Dame, police said.
Police officers are at the school and officials say students are not in any immediate danger. Parents are asked not to call the school, as phone lines must remain open, and not to pick up students unless there is a previously arranged appointment.
“Know that we will communicate out to you with an update shortly. As always, safety of all students is our primary concern,” reads a statement from Notre Dame Principal Patrick Browne.