Parents who flocked to the school were given the option to sign out their children after speaking with them. Several did, with the assistance of borough officers, Police Chief Cathy Madalone said.
The district "immediately followed" all guidelines in locking down the school and notifying police around 8:20 a.m. after interim Principal Shane Biggins received a report that the 13-year-old Hackensack boy was on the premises of the middle school, Assistant Schools Supt. Christopher Tully told parents who'd gathered across the street (SEE video, above).
The school was searched with no danger to anyone, Madalone said.
The boy's 12-year-old sister was found in the high school around 10:30 a.m. and taken into custody, school officials said.
A search continued for her brother, who was found at his parents' home, the chief added.
He and his sister will be prosecuted "to the fullest extent of the law," Tully told parents outside the school before normal operations resumed at 12:30 p.m.
"We want the students to go back to having as much of a normal day as possible," he said.
Joining Bergenfield police at the scene were their colleagues from Dumont and Tenafly.
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