The 47-year-old suffered a fractured knee
British TV presenter Richard Hammond was seconds from being "incinerated" in a car crash, according the producer of his programme.
Andy Wilman, who helps put together 'The Grand Tour', said the star was lucky to be alive after his vehicle flipped and burst into flames in the Swiss mountains.
The 47-year-old suffered a fractured knee while racing an electric super car, but was not seriously injured.
Hammond's co-stars on the show, Jeremy Clarkson and James May, arrived on the scene shortly afterwards.
Mr Wilman told the Sunday Mirror: "Jeremy and James both raced down to the scene of the crash as soon as it happened.
"When they saw the wreckage on fire they thought Richard was dead. It was really bad.
"They were staggered he had got out of it alive, because there was just nothing left."
Clarkson described it as the "biggest" and "most frightening" crash he had ever seen, adding in a Twitter post: "Thankfully, Richard seems to be mostly OK."
It was the biggest crash I've ever seen and the most frightening but incredibly, and thankfully, Richard seems to be mostly OK.— Jeremy Clarkson (@JeremyClarkson) June 10, 2017
A spokesperson for 'The Grand Tour' said: "Richard was conscious and talking, and climbed out of the car himself before the vehicle burst into flames.
"He was flown by air ambulance to hospital in St Gallen to be checked over - revealing a fracture to his knee.
"Nobody else was in the car or involved in the accident, and we'd like to thank the paramedics on site for their swift response.
"The cause of the crash is unknown and is being investigated."
Hammond was racing a Rimac Concept One car, built in Croatia, during the Hemburg Hill Climb.
It was filmed as part of the second series of The Grand Tour, the Amazon Prime programme Hammond, Clarkson and May joined after leaving the BBC's Top Gear in 2015.
According to the car manufacturer's website, the Concept One can reach a maximum speed of 220mph thanks to its 1,224 horsepower motor.
The Hemburg Hill Climb takes place over a one-mile-long course, which climbs 157m (515ft).
In 2006, Hammond suffered brain injuries after crashing a jet-propelled car while travelling at close to 300mph.
The horror accident left him in intensive care, where he was in a coma for two weeks.
Clarkson issued an apology to Irish producer Oisin Tymon back in 2016, after he was attacked in a row over food at a North Yorkshire hotel.
It resulted in Mr Clarkson losing his job and subsequently the break-up of the Top Gear line-up.
A settlement of stg£100,000 (€126,622) for racial discrimination and personal injury was also reached.