Local streets on and around River Road and Main Street were jammed with traffic past 4:30 p.m.
"We have no specific credible evidence of anything more than this anonymous threat," Bergen County Sheriff's Public Information Director William Schievella told Daily Voice an hour earlier.
"But our protocol in all instances is that we clear the building completely and thoroughly search with our Bomb Squad and K-9 units," he said.
The call came in just before 3:30 p.m. on a sunny day with temperatures in the mid-80s.
Court and non-emergency staff and occupants who were temporarily housed in another facility were expected to leave the building for the weekend.
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