Authorities say the burglaries took place during the Berkeley School Charity Walk-A-Thon in Westvale Park on Sunday, March 31, within a 10-minute time frame around 1:30 p.m.
The vehicles -- which were all locked -- had their windows smashed, and valuable were removed.
As a result of the thefts, police are asking civilians in Bergen County to keep their vehicle doors locked at all times and valuables out of sight.
"Even if you lock your car, do not leave your valuables out in the open," the police chief said. "Take them with you if you can or hide them."
A photo was released of a sedan police believe may have been involved with the burglaries.
Police say the incidents may be connected to a gang from Florida that recently moved into the area and is believed to be responsible for similar incidents in four New Jersey towns, including Hoboken.
The investigation is ongoing.
Anyone who might have seen something, has images from the event facing the parking lot, or has information that could help identify those responsible is asked to contact the Westwood Police Detective Bureau at (201) 664-7008 or email firstname.lastname@example.org.
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