Police found a ghost gun in a car at New Milford High School Tuesday morning.
Officers responded to the school around 9:20 a.m. after the report of a weapon on school property.
The school was placed into lockdown and police worked to locate the students involved.
According to police, there was a fight in a bathroom at the high school Tuesday morning which led to information about a gun on school grounds.
Officers searched the car of one of the students and found a loaded 9mm pistol with no serial number, police said.
The 17-year-old student was charged with criminal possession of a firearm and possession of a ghost gun. Police did not release the individual's name due to the student's age.
Two other students were arrested in connection with the earlier fight.
The lockdown was lifted around 11 a.m.
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