Officers responded to the area of Brass Castle School in Washington and patrolled the grounds shortly before 12 p.m., the township police department said alongside the school district.
Witnesses who were walking at Meadow Breeze Park confirmed reports of gunfire coming from north of the mountain as well, police said.
The search yielded negative results, and the shelter-in-place was lifted about an hour later.
“Thank you to the Washington Township Police Department and our SROs for always keeping our schools safe,” Superintendent Keith Neuhs said.
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