The "inert device" found in the upper level's eastbound lane next to the median on the New Jersey side had a pipe bomb casing -- a symmetrical cylinder with two tied caps at either end -- but not all of the other components necessary to make it explosive, investigators said.
Whoever called in the report may have been the person responsible for placing it there, investigators suspect.
It was the only call police received, and the rain made it extremely difficult to see the roadway, they explained.
Ordinarily, those who place bogus devices are testing the police response, though it was initially unclear what the motivation may have been.
"Either way, it makes people nervous," a law enforcement source told Daily Voice. "There could have been an accident caused by panic -- and even a fatality.
"We don't need that."
The Bergen County and NYPD bomb squads were among the responders, along with a Bergen hazardous materials unit.
A Port Authority police investigation was continuing.
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