An American Airlines flight carrying 179 people from Manchester to Chicago has been diverted to Bangor, Maine, because of security concerns.
The Transportation Security Administration said it learned of a reported threat to the aircraft while it was en route.
The FBI said the plane landed safely at Bangor.
An aviation industry source confirmed that the alert was caused by a suspect name on the list of passengers.
He said: 'Airlines flying from the UK to the USA are required to send the passenger manifest to the US Homelands Security department, which checks the names and then releases the plane for take-off.
'On this occasion, a suspect name has come up but for some reason the alert was not sent out or received until the plane was in the air.
'At this stage, it is unclear why that happened.'
Meanwhile, a new survey has meanwhile shown that nearly a third of Britons are now less likely to fly to the United States because of increased security surveillance.
The ITV survey comes as 1.7 million passengers are expected to pass through UK airports this weekend for the late summer bank holiday.