An American Airlines plane flying from London to Miami was forced to turn around and head back to Heathrow after it declared a mid-air emergency.
Flight AA57 is believed to have turned around in the English Channel.
AirLive reported that the plane had suffered a "maintenance issue".
Flight Emergencies later tweeted that the plane had since landed at Heathrow.
There are no reports of any injuries.
American Airlines tweeted saying its maintenance team will be on the ground to inspect the aircraft and it is hoped the flight will take off again at 1pm.
More to follow.