Three of those passengers set off the detector's alarm and continued to their gate. Their carry-on bags were placed on a conveyor belt and screened by a TSA officer.
According to a statement from the Port Authority of New York and New Jersey, the incident occurred sometime between 5 a.m. and 6 a.m. at JFK's Terminal 5 at a TSA PreCheck checkpoint. It took TSA two hours to notify the Port Authority of the security breach.
JetBlue declined comment and referred ABC News to TSA.
In a statement, the TSA said there was a "possible security incident" and that "early reports indicate 3 passengers did not receive required secondary screening after alarming the walk through metal detector."
"TSA conducted security measures at the passengers' arrival airport. TSA works with a network of security layers both seen and unseen. We are confident this incident presents minimal risk to the aviation transportation system," the statement added. "Once our review is complete, TSA will take appropriate action.”