NewsCopter 7 was over Hackensack High School where police say an 18-year-old man was injured.
The victim was treated at the school and then brought to a local hospital with non-life-threatening injuries.
Officers have a suspect in custody. Juvenile delinquency charges are expected to be filed.
It's unclear what sparked the stabbing.
If anyone has any information, they are asked to call CrimeStoppers at 844-466-6789. You can call 24 hours a day, 7 days a week. You can also remain anonymous.
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