Washington (CNN) Law enforcement scrambled on a busy long weekend travel day to ensure airplanes were secure after at least 10 threats were phoned in threatening flights.

The first sign of trouble came when NORAD scrambled two F-15 fighter jets over the Atlantic to escort Air France flight 22 to New York's John F. Kennedy airport after Maryland State Police reported getting a threat about the Paris to New York flight.

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Police officials radioed the crew to ask if anyone on board had been sick during the flight, according to air traffic audio reviewed by CNN. When the crew responded everyone was fine, everyone was evacuated from the plane and its contents were searched. Nothing was found.

One passenger said those on board didn't know anything was wrong until they landed.

"In the air, nothing. In the air we didn't feel nothing. Just when we landed and they stopped us. This is when we know that something is wrong," Eylon Benzeeb told CNN.

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