Authorities said they were contacted about the threat on Tuesday, March 19.
"The investigation is ongoing and there is a collaborative effort between the police department and the school district to ensure the safety of the students and staff of Saucon Valley School District," police said in a release.
"In an effort to not impact the ongoing investigation, the further release of information will be restricted."
Anyone with information is asked to call Lower Saucon police at 610-317-6110 or submit a tip through Crimewatch.
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