The student was treated for the minor injury by EMTs and during the lockdown, which had ended as of 9:55 a.m., Parsippany police said.
The lockdown was in response to a perceived threat at Parsippany Hills High School, the BOE said.
"The situation has been secured and Parsippany Police are handling the matter," the statement says.
The PHHS lockdown is separate from the Morris County School of Technology lockdown, which students on Snapchat said was in a response to a shooting threat.
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