Local police arrived at the school after someone called in the threat around 2 p.m., Newtown Township police said.
The school was evacuated to an alternate site while officers searched the perimeter, and concluded the investigation around 2:40 p.m., police said.
School activities resumed as usual after the search, police said.
Superintendent of Schools Dr. Robert Fraser was on location and advised of the situation, police said.
Newtown detectives were continuing the investigation to determine the source and identity of the caller, police said.
"As always, the Newtown Township Police Department would not be capable of fulfilling our mission without the support and partnership of our citizens," said John L. Hearn, Chief of the Newtown Township Police
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