Members of the Glen Rock High School Class of 2021 went on a destructive rampage, which the principal called "disgraceful," during a post-commencement event called Grad Ball on Friday.

Glen Rock police said they are investigating criminal mischief and theft that occurred at the school including the destruction of a statue of the school's panther mascot.

Video provided by police shows knocked-over folding chairs and spilled planters in the field.

Police Chief Dean Ackerman said about 100 students gathered around the borough in the early morning hours of Friday, including tracks on NJ Transit's Main-Bergen Line. NJ Transit's Twitter account for the rail line does not show any service delays on Friday morning.

In a letter to parents, principal Michael Parent said he was "heartbroken" by the actions of students who had just received their diplomas, according to the Daily Voice. Parent said he realized they did not represent the entire class.

Parent on Tuesday morning did not respond to New Jersey 101.5's request for more information.

Ackerman said the investigation by police is ongoing and asked anyone with video of the vandalism to contact his department at 201-670-3948.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com or via Twitter @DanAlexanderNJ

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