Officers responding to the call in the Allwood section around 9 p.m. Monday chased the troubled 16-year-old boy to Jubilee Park, Lt. Robert Bracken said.
Area traffic was blocked while the officers tried to reason with him, Bracken said.
The teen was "extremely agitated," however, and refused to drop the knife at first, the lieutenant said.
Instead, he repeatedly stabbed a nearby tree and threatened to cut his wrists, Bracken said.
Officers eventually convinced the boy to drop the knife after about a half hour, the lieutenant said.
They took him into protective custody after a brief struggle and then delivered him to St. Joseph's Regional Medical Center in Paterson for a psychiatric evaluation and treatment.
No one was injured and no complaints were filed, Bracken said.
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