A formal investigation has been launched after a plane crash landed at Heathrow this afternoon.

The plane crash landed short of the runway at the airport narrowly missing a busy road and leaving massive skidmarks in the grass.

Reports suggest the plane suffered single engine failure, loss of hydraulics and was running on one engine.

An airport source said it was lucky not to have come down over London.

Investigation

BA's chief executive, Willie Walsh, told a press conference today a formal investigation was being carried out by the air accident branch of the Department for Transport.

He said it would be inappropriate to speculate on the likely cause of the incident, but praised the efforts of the flight crews and the emergency services.

"Enormous bang"

John Rowland, a Hounslow cab driver on his way to the airport, told the BBC: "The plane's wheels collapsed, doors were flown open.

"On its approach it took the runway too low, just missing the roof of my cab.

"It crashed into the runway, debris was flying everywhere, there was an enormous bang and it skidded sideways."

The plane hit the ground several hundred yards short of the southern runway, severely damaging the undercarriage, wings and engines.

Six injured

Six people were injured in the emergency landing.

A spokesman for the ambulance service said there were eight ambulances at Heathrow and six passengers had been taken to nearby Hillingdon Hospital with minor injuries.

She could not give details of the type of injuries the passengers suffered.

Southern runway reopened

The airport's southern runway was closed immediately after the incident but has now been re-opened for take-offs.

The northern runway is operating for arriving aircraft.

Emergency chutes

Eyewitness reports say passengers escaped down the emergency chutes after British Airways flight BA38 from Beijing came down.

The incident caused the delay of Prime Minister Gordon Brown's flight to China.

British Airways has confirmed that a Boeing 777 operating flight BA038 was involved in an incident at Heathrow.

Patrick Spink from British Airways press office said the planes are the newest in the company's fleet. He was unable to confirm the cause of the crash.

British Airways chief executive Willie Walsh said: "We are very proud of the way our crew safely evacuated all 136 passengers on board with only three minor injuries."

There were three flight crew and 13 cabin crew on board.

In a statement, the Civil Aviation Authority said: "The incident will be investigated by the Air Accidents Investigation Branch of the Department for Transport and the CAA is offering assistance to all organisations involved."

London Fire Brigade is currently attending the incident after being called at 12.43pm.

A spokesman said: "No fire has been reported and fire crews are standing by."

BA has set up a helpline for friends and relatives on 0800 3894193.

Flights cancelled

Some short and long-haul British Airways flights have been cancelled, particularly any departing from Terminal 4.

Customers are advised to check the status of their flight before they leave for the airport.

In total the airport has said 91 flights had been cancelled by 3.30pm.

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