The gang of four -- all in their late teens to early 20s -- entered the convenience store at the Essex Street service station just off Routes 80 and 17 shortly after midnight, Lt. James M. DePreta said.
The one with the knife and two others approached the cleark, took the cash from the register and grabbed cigarettes and cigars, as well, he said.
They headed toward High Street, where a vehicle apparently was waiting, DePreta said.
Anyone who might have witnessed the robbery or has surveillance video or information that could help Rochelle Park detectives working the case is asked to call them at (201) 843-1515.
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