Police found no credible threat and students and staff returned to the school around 2:15 p.m., Detective Andy White told Daily Voice.
The threat stated that the writer hates Passaic High School and there was a bomb in the courtyard, White said.
Passaic County Sheriff's Office Bomb Squad and K-9 units investigated and students were temporarily moved to the middle school and School No. 11, the detective said.
Authorities did not know when the threat was written, he said.
Threats also forced school evacuations in Passaic in late January and early February.
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