American Airlines flight AA732 was diverted several hours into a trip from Charlotte to Heathrow.
It has turned around over the Atlantic and has now been diverted to Philadelphia.
The plane is now passing Nova Scotia, Canada, as it makes it way back from the Atlantic Ocean to the US east coast.
No reason has been given for the diversion. The flight is due to land at Philadelphia at around 10.15am GMT.
This is a developing story, more to follow…