LONDON // At least seven people were killed and 51 injured in a major pile-up involving 34 vehicles in south-west England.
The crash on Friday night resulted in explosions, with vehicles burning "literally to the ground", said assistant chief constable Anthony Bangham.
Police expect the death toll to rise and fear they may find more bodies in the wreckage.
Witnesses heard explosions and saw debris and casualties strewn across the road.
Dozens of firefighters battled to free people who were trapped in the wreckage of their vehicles on the northbound carriageway.
Footage shown on British news channels showed large balls of fire consuming lorries and billowing smoke.
It was not immediately clear what caused the collision on the M5 motorway but police said foggy conditions and wet road surfaces were partly to blame.
"It was quite horrific and I have never seen anything like that. I could see people lying on the side of the road," one motorist, Paul O'Connor, told Sky News television.
Road accidents of this scale are rare in Britain and rescuers have described the pile-up as one of the worst in living memory.
The affected section of the busy motorway was closed in both directions as police removed all vehicles for forensic examination.
The road was not due to be reopened until today at the earliest, police said.
