A British Airways flight has been forced to make a sudden landing after a technical issue was declared.
Flight BAW67V bound for the east coast of the United States has been diverted to Heathrow airport.
It is the second BA aircraft forced to land within two days under the Squawk Code 7700 which is generally used by pilots to request a priority landing into a busy airport, allowing them to skip the queue.
Airport webcams reported that the Boeing 777-36N(ER) climbed 12,000ft and then returned to Heathrow instead of completing its journey to Philadelphia.
The plane was tracked by Live Air Traffic website flightradar24 as it appeared to land at the West London Airport at around 2.45pm on Tuesday.
BA confirmed that the plane landed safely and that it was not an emergency but a priority landing due to a technical issue, with online reports suggesting this may have been due to a "pressurisation problem."
Staff have arranged for a replacement aircraft to fly passengers to Philadelphia later on Tuesday.
The unexpected landing comes just one day after BA flight 1496 from London to Glasgow was forced to declare a mid-flight emergency.
Concerned pilots took action due to technical issues and an emergency was declared at around 11pm on Monday.
The plane, which usually has a flight time of one hour and 25 minutes, took off from London Heathrow Airport at 9.56pm.
Global tracking network Plane Finder showed a recorded map of the aircraft's route as it circled twice over Lanark and Carluke before heading north and turning back on itself towards Glasgow Airport.
A BA spokesperson told the Mirror Online: "The pilots requested a priority landing as a precaution due to a technical issue and the aircraft landed safely."
According to Airport Webcams, the diverted flight was a British Airways BA67 London Heathrow to Philadelphia (Boeing 777-300ER G-STBB).
It was scheduled to take off from Heathrow at 12.40pm UTC, and land in Philadelphia at 8.35pm UTC.
After departing from Heathrow 16 minutes late at 12.56pm, it was forced to turn back around and landed at Heathrow around 2.45pm.
Airport Webcams tweeted that the aircraft "stopped the climb at 12,000ft, declared Pan Pan, squawked 7700 General Emergency due to a pressurisation problem (via ATC) and has just returned to LHR."
