Two youngsters told a teacher just after 12:30 p.m. that they "observed a male individual, wearing a dark colored hooded sweat shirt with the hood up, enter the school through an open window in the 3rd wind portion of the building," Elmwood Park Police Chief Michael Foligno said.
The school was placed into lockdown for about an hour and 40 minutes while officers from the borough, Garfield and the Bergen County Sheriff's Office established a perimeter and searched the building.
Authorities also reviewed surveillance video that showed the trio, Foligno said. They also interviewed the witnesses, he said.
"There were no weapons involved and no one was injured during the incident," he said.
Police weren't bringing juvenile complaints against the youngsters, the chief said.
However, he said, "the situation will be handled accordingly at the school district level."
The lockdown was lifted at 2:18 p.m.
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