Swiss police have said the fatal wingdiving accident occurred among a group who were in the region as guests of a company that makes extreme sport films for the internet.
Although police have yet to confirm the victim's identity, he is understood to be Olympic stuntman Mark Sutton.
Police, though, said: "The victim, a Briton, was 42 years old. He was staying in Chamonix (in France) with 20 followers, considered among the best in the world in this discipline."
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