Port Authority police say they received the reports of shots fired at Terminal 8 near the departures area around 9:30 pm (local time) yesterday.
The New York Police Department was called in to assist. There were no reports of any injuries or arrests.
Police say they have not been able to confirm whether any shots were actually fired. They evacuated the area as a precaution.
A short time later, police say they closed Terminal 1 after there were additional reports of shots fired. An expressway approaching the airport also was shut down.
The investigation is ongoing.