It happened around 7:45 p.m. Friday at Virani Jewelers on Oak Tree Road in Iselin.
Police say that as the store was nearing closing time, an armed group of people wearing masks and gloves followed an employee through the front door.
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The suspects then forced store employees to the floor before smashing multiple glass display cases with hammers.
They emptied the cases, taking off with the jewelry inside.
The thieves fled before police could arrive, with the entire robbery taking less than one minute.
The worth of the stolen goods has not yet been determined, but the owner of a neighboring business tells Eyewitness News that the thieves made off with more than $1 million in jewelry.
There are at least 10 to 15 other jewelry stores in the surrounding area, and there is no word on recent robberies from those stores.
Anyone with information is asked to contact Woodbridge Police Detective Perry Penna at 732-624-7700.
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