An increased police presence at Palisades Park Junior/Senior High School on Tuesday will be among the measures taken after a "non-specific" threat was found scrawled on a desk.
Students also will be able to enter the school only through the front doors, Schools Supt. Joseph Cirillo said Monday.
School officials were working with police to determine who wrote the graffiti found on a desk in a classroom, Cirillo said.
"Please discuss the ramifications of such a threat with your child," the superintendent wrote to parents.
He also urged them to call police if they or their children have information that could help find whoever was responsible.
"The safety and well-being each student, faculty and staff member is paramount to our district and all threats credible or not will be taken as such," Cirillo wrote.
Palisades Park officially began having armed retired police officers in the schools the past two weeks in response to the Parkland, FL school shooting.
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