A transatlantic flight from Manchester was diverted to an airport in the far north-east of the United States last night after a reported threat.
American Airlines Flight 55, en route to Chicago, was diverted to Bangor Airport in Maine.
Transportation Security Administration spokeswoman Andrea McCauley said: "We learned of a reported threat to the aircraft while it was en route." She said FBI agents were interviewing passengers and crew members.
Also yesterday, a US Airways jet flying to North Carolina was diverted to Oklahoma City after an air marshal subdued a passenger involved in an incident with a flight attendant.
And an Aer Lingus flight from New York to Dublin was evacuated at Shannon in western Ireland following a threat against the aircraft.