Garfield patrol and ESU officers, along with two officers from the Bergen County Regional SWAT Team, secured the school, Capt. Darren Sucorowski said.
"Detectives from the Garfield Police Department conducted an investigation and were in contact with other agencies investigating similar incidents," the captain said. "As a result of the investigation, it was determined that there was no credible threat against Garfield High School.
" The information was relayed to the school administrators and the shelter in place was lifted."
Several North Jersey schools -- mostly vo-techs -- had lockdowns Friday morning for precautionary measures, authorities said.
Any and all threats were deemed not credible.
The first reported lockdown was at the Morris County School of Technology, whose students posted videos of what was happening.
Bergen County Tech in Paramus and Parsippany Hills High School were briefly in lockdown mode.
A "screenshot of an indirect threat" also put the Passaic County Technical Institute in Wayne into lockdown.
Passaic County Sheriff Richard H. Berdnik said through a spokesperson that "out of an abundance of caution, we increased patrols in and around the school and are closely monitoring the situation."
Such incidents can alarm students, parents and staff.
A Parsippany High School student cut himself trying to jump out a first-floor window during the lockdown there. A teacher at another school grabbed a knife and stood outside his locked classroom's door.
Law enforcement officials nonetheless unanimously agree that even the perception of a threat -- no matter how remote -- should be treated seriously.
"In this environment and the way things are, we can't take anything lightly," one said. "It's easier for us to make sure nothing happens," one said. "In the end, it's well worth doing."
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