The main gate security guard at Soundview Paper Company told responders that a caller just before 10:50 p.m. said aid there were bombs in three buildings.
A second main gate security guard got a similar call 10 ninutes later, "advising that there were several devices" in the buildings, Police Chief Michael Foligno said Wednesday morning.
"Neither recognized the caller's voice," he said.
Foligno's officers helped Soundview security evacuated the Market Street plant.
Bergen County Sheriff's bomb-detection dogs swept the buildings and found nothing. After about two hours, the plant was declared safe, the chief said.
Anyone with information that could help identify the caller or callers is asked to notify Elmwood Park police; (201) 796-0700. Callers may remain anonymous, Foligno said.
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