Two F-16 fighter jets were scrambled to escort a flight from Los Angeles to John F. Kennedy Airport Sunday afternoon after passengers refused to come out of a bathroom.
The flight landed safely after 4 p.m.
The Transportation Security Administration said in a statement that it was "notified of passengers allegedly behaving suspiciously" onboard the flight at about 3 p.m., and that the jets were scrambled "out of an abundance of caution."
The passengers on American Airlines Flight 34 went into a bathroom and were "not compliant," a security official told NBC New York.
Several sources tell NBC News that three passengers were drunk and refused to follow flight attendant instructions, making long and frequent visits to the lavatories.
American Airlines spokeswoman Andrea Huguely said the flight proceeded with normal landing after the flight captain and crew assessed the situation "and did not see any cause for alarm." The airline stressed that it did not request escorts or extra security at JFK upon arrival.
The three men were later questioned and released at the airport, an FBI spokesman said.
Passengers told NBC New York after landing that they didn't even know there was an incident on board until they saw police meeting the flight on the ground.
New York City has been under heightened alert since intelligence was picked up overseas indicating a possible plot to coincide with the 10th anniversary of 9/11.
U.S. military officials tell NBC News that the intercept was "normal" and required no other action from the pilots other than to escort the plane.
One military official told NBC News that military jets were in the air over New York and Washington as a matter of routine precaution for 9/11.
It's not clear whether these two F-16s were part of that air patrol.