Upper St. Clair School District parents were alerted on Monday that a general threat made against the district was a part of a national hoax.

The school sent out an email stating that school district officials learned of the incident in the morning. Local and federal law enforcement agencies verified that students and staff were safe.

While the incident was a “hard start to the week,” said Tina Vojtko, a spokeswoman for the school district, all Upper St. Clair schools were cleared to operate on a regular schedule with precautionary measures in place.

Under the secured status, schooling and classes continue within the building, while all students and staff remain indoors and only visitors with an appointment may enter a school, according to the letter that was sent to parents.

“As always, we are grateful for the willingness of our students and families to share information with school officials and/or law enforcement. The most important component of our school safety plan is ongoing, open communication. Simply put, if you see something, say something,” the email to parents said.

The investigation was ongoing Monday morning, and the school district said that in order to potentially identify the source, it will continue in order to pursue legal action.

Officers at Upper St. Clair Township Police Department directed questions to the school district.

School district officials declined to provide comment on the nature of the national hoax.

Pittsburgh’s FBI office did not respond to an immediate request for comment.