A British Airways plane has had to return to Heathrow with smoke billowing from the aircraft.
With eyewitnesses reporting seeing an engine on fire, the Airbus A319 plane made an emergency landing, with the 75 passengers and crew all safely evacuated via the emergency chutes.
London Ambulance service later reported that three people had been treated for minor injuries from the flight, which had taken off from Heathrow for Oslo on Friday morning. Both the northern and southern runways at Heathrow were closed after the incident, although flights were able to resume shortly afterwards from the southern runway.
Eyewitnesses described seeing smoke coming from the plane, with the right engine on fire.
Clive Cook, who lives on the Heathrow flight path, told Sky News: "The actual engine itself was on fire. This plane was coming over and suddenly the tone of the engine changed dramatically, and I could almost say it sounded as if it was like a blowout, or an explosion. I'm absolutely certain that as it came through the clouds, and I looked up ... the right engine was on fire, it wasn't smoking, it was actually on fire."
A BA statement said: " BA762, Heathrow to Oslo service, returned back to Heathrow shortly after take-off due to a technical fault. The Airbus A319 aircraft was carrying 75 customers.
"The aircraft landed safely and emergency slides were deployed and we are currently caring for our customers. Emergency services attended the aircraft. We will be carrying out a full investigation into the incident."
There was speculation that the aircraft may have run into a flock of birds but there was no official confirmation of this. Following the incident, passengers on resumed flights at Heathrow were warned to expect delays of up to 60 minutes and extended aircraft taxiing times.
BA said the plane, with two pilots and three cabin crew aboard, had taken off for Oslo at 8.16am and had landed back at Heathrow just after 8.40am. "The passengers are being looked after at the moment," said a BA spokesman.
The incident is being investigated by the Air Accidents Investigation Branch.