A woman passenger has been arrested after a flight from London to Washington was diverted to Boston because of an on-board disturbance.
Security checked every piece of luggage from the flight
Transport officials said the 59-year-old woman was held in connection with a confrontation with the flight crew.
She was carrying hand cream - a banned item - and matches on board the United Airlines flight.
The aircraft was escorted into Logan airport by two jet fighters.
Responding to reports that the woman had been tied up during the flight, United Airlines spokesman Brandon Borrman said that she had been restrained.
"Safety and security are top priority. Crews are trained to restrain when they feel it is appropriate for the safety and security of the flight," he said.
Reports that the woman was carrying a screwdriver and a note referring to al-Qaeda have been denied.
Security officials at Boston's Logan International airport laid all of the luggage from the plane out on the runway and checked every item with sniffer dogs.
The woman, who is from Vermont, is expected to be charged on Thursday.
However, US Attorney Michael Sullivan's office said, in a statement, that "at this time, there is no evidence that this was a terrorist-related incident".
United Flight 923 from Heathrow Airport, with 182 passengers on board, was originally bound for Washington DC's Dulles Airport.
It landed at Logan at about 1020 local time (1420 GMT).
Nenette Day, a spokeswoman for the Federal Bureau of Investigation in Boston, said the woman passenger was apparently claustrophobic and had become disruptive on the flight.
"This isn't just an 'I want another drink kind of thing,' it was a disruption that caused them to divert the plane," she said.
The incident comes almost one week after an alleged bomb plot targeting UK flights to the US was uncovered by British intelligence officers.
One of North America's largest ship container terminals was evacuated on Wednesday after bomb-sniffing dogs became alarmed by two cargo containers from Pakistan.
No explosives or chemical or biological agents were found in the containers in Seattle, the US customs and border protection service said.
One was filled with clothes and the other with large bundles of used or recycled textiles.