A large police presence was reported at the school in the early afternoon.
A Chester County official said authorities were responding to a threat directed at the school but declined to comment further.
Students were moved to the football stadium as authorities swept the building, the outlet said.
The school canceled its homecoming football game on Oct. 7 after an online threat was deemed "credible" by law enforcement. The school was searched for weapons by police canine units on Thursday, Oct. 13, and another threat was received on Friday, Oct. 14.
Police were not immediately available for comment. This is a developing story.
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