The Lakeland High School resource officer, Detective Sgt. Phil Cavallaro, was at the Monday afternoon meeting with Detective John Galinus when they noticed the knife, Capt. Ken Fackina said.
"When questioned about the knife, he admitted to having it but refused to turn it over," Fackina said.
Cavallaro tried to grab it, but the teen resisted and ran, but he "was taken to the ground by both detectives and arrested," the captain said.
Besides the weapon, they recovered marijuana, crack and a scale, he said.
No other students were around at the time, Fakina said.
The teen was taken to St. Joseph's Regional Medical Center before being released to his mother.
A delinquency complaint was being prepared accusing the boy of having drugs and a weapon, as well as resisting arrest.
A hearing in the Family Division of Superior Court in Paterson was being scheduled.
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