Pilots on a British Airways flight have taken oxygen not long after departure from Heathrow Airport.
Flight tracking sites said the plane destined for Nice, France, initiated the 7700 squawk code shortly after takeoff around 5.22pm and returned to the airport.
The code indicates an on-board emergency requiring priority attention from a nearby airport.
And it came after passengers reported an unusual odor emanating from the aircraft.
Crews reportedly raised the alert for “fumes” in the cabin, with passengers smelling “strange smells”.
Writing on Twitter, Sebastien Mezeret said pilots were given “oxygen masks”.
He added the plane returned to the airport surrounded by fire crews, but there was “no intervention” and pilots were “still on oxygen”.
A BA spokesman said the plane had looped back after experiencing a technical issue.
They added: “The aircraft landed normally after returning to Heathrow following reports of a technical issue.
“The safety of our customers and crew is always our priority.”
Passengers are waiting for a replacement aircraft to continue their journey to the south of France.
More to follow…