At least seven people died in one of Britain's worst ever motorway pile-ups, police said Saturday, as investigators probed the cause of the crash which triggered a huge fireball.
Footage taken at the scene showed motorists risking their own lives amid the flames to prise open vehicle doors and rescue people trapped inside.
The 34-vehicle crash in foggy and wet conditions on the M5 motorway near Taunton in southwest England sparked explosions and an inferno, reducing vehicles to cinders and leaving twisted, fire-blackened metal scattered across the carriageway.
Emergency services said 51 people had been injured and warned the death toll was likely to rise.
Witnesses described hellish scenes, with multiple explosions and towering flames sending a pall of acrid smoke over the motorway.
"We could hear people screaming in their cars. It was utter carnage," said motorist Thomas Hamell, 25, who narrowly avoided the carnage as he came to an abrupt halt next to a jack-knifed lorry at the edge of the crash site.
"We sat there and heard the thud of cars, one after another, hitting each other and thought we would be next."
As a search of the burnt-out vehicles continued, a large section of the route through England's southwest was set to remain closed in both directions until Sunday, causing long delays for motorists.
Assistant Chief Constable Anthony Bangham of the Avon and Somerset Constabulary told reporters: "Sadly I can now confirm that we believe we've had at least seven people die as a result of this incident.
"I am also able to confirm that we've got 51 casualties. Many of those have gone to hospital."
He said 34 vehicles were involved in the accident on Friday evening, "many of which are burnt -- and burnt literally to the ground."
While casualties have been taken to two nearby hospitals and some treated at the scene, Bangham said others might still be trapped.
Edmund King, president of the Automobile Association, said it was Britain's worst traffic accident in two decades, the last comparable incident being a 51-car crash on the M4 motorway in March 1991 in which 10 people died.
Hospitals said the injuries ranged from simple limb fractures to more complex chest and abdominal trauma.
Bangham said detectives would be examining the possible factors involved, including the darkness, fog and groundwater, plus a fireworks display close to the three-lane road.
"All we could hear was the sound of a horn and then the flames got so high so quickly and the noise was horrific," said Bev Davis, who saw the pile-up from her home close to the motorway.
"There must have been 200 metres (660 feet) worth of fire -- plumes of smoke were going up and everything was red."
Motorist Paul O'Connor told Sky News television: "It was quite horrific and I have never seen anything like that -- I could see people lying on the side of the road."
But tales of bravery also emerged amid the horror. Hamell said that he had managed to carry a baby to safety as chaos raged around him.
The teacher described how he and his two travelling companions managed to get safely out of their car at the edge of the accident and help a mother and her young baby, whose car was severely damaged in the carnage.
"We were incredibly lucky. The woman who gave her child, her car was wiped out," he said.
