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.
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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.
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The lockdown was lifted around 11 a.m.
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