At least two people were killed and 11 others injured when a helicopter crashed into a crane on top of one of Europe's tallest residential blocks in central London and plunged to the ground in a ball of flame during rush hour today.
The helicopter was reported to have been carrying a pilot but no passengers. It struck the ground just 20 yards from Vauxhall station, a major commuting hub in the capital.
One witness said the helicopter struck the side of the St George Wharf Tower, Britain's tallest block of flats currently under-construction, near the river Thames, as it fell to the ground. The fate of the pilot is not known.
"Two people have died and 11 taken to hospital. Details are awaited," a Metropolitan Police spokesperson told PTI.
At least two cars were hit by debris from the crash.
A motorist is in hospital after being rescued from a burning car by fire crews.
The helicopter involved is believed to be an Augusta 109 model.
Eight fire engines, four fire rescue units and around 60 firefighters were at the crash site with the police and ambulances.
Burning wreckage lay in the road but firefighters have brought the fire under control.
The police said in a statement that they had been alerted at approximately 8 am (local time) this morning to an incident at Wandsworth Road.
"At this early stage it appears a helicopter was in a collision with a crane on top of a building. Met officers, the ambulance service and the London Fire Brigade have attended," a Metropolitan Police statement said.
Dense black smoke was billowing from the area after the helicopter spiralled to the ground in what eyewitnesses told Sky News looked like "a massive ball of flame".
Soon after the accident, the Air Accidents Investigation Branch.
The Metropolitan Police have said that the helicopter is not one of their fleet.
The incident caused gridlock with all approaches to the Vauxhall Cross one way system closed at the height of the rush hour and Vauxhall Tube station and railway station closed.
A spokesperson for London Mayor Boris Johnson said: "This is clearly a major incident involving considerable numbers of emergency service personnel".
"The mayor's thoughts are with the families of the two victims and with those injured. The Mayor has spoken with Met Police Commissioner Bernard Hogan Howe and Transport Commissioner Peter Hendy," he said.
"He remains in close touch with all his Commissioners and he will continue to monitor the situation closely," he added.
Witnesses described scenes of "absolute madness and fear".
They reported cars on fire and people screaming.
A spokesperson for London Fire Brigade said the crane was "in a precarious position".
As investigations begins into the fatal crash the focus will be on strict rules surrounding helicopter flights over the city.
The AAIB will be looking into the events leading up to the incident and whether proper procedures and routes were followed.
All those flying helicopters in London have to follow a set series of routes laid down by the Civil Aviation Authority (CAA).
Helicopter pilots flying over the city are subject to air traffic control clearance and must have twin-engine aircraft.
Those flying one-engine aircraft must follow the route of river Thames.