Lehigh Career and Technical Institute in Schnecksville alerted police after receiving "a threat directed at the school," administrators said in a message on the school's website.
Classes are scheduled to resume normally on Monday, Oct. 31, they added.
The warnings came exactly two weeks after LCTI students and staff participated in a six-hour active intruder security drill, according to a post on the school website.
State police are investigating the matter, WFMZ reports.
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