Talented Swiss snowboard champion Estelle Balet was killed in an avalanche in the Alps while on a film shoot on the Swiss-French border. Balet, who was snowboarding above the Swiss village of Orsières when the avalanche struck, was swept down a narrow, rocky slope. She was following another boarder who was not caught in the avalanche.

Balet was wearing safety equipment including a helmet, a location device and an airbag to help stay above sliding snow in the event of an avalanche, The Guardian reported. Rescuers managed to locate the 21-year-old snowboarder and dug her out from the snow, but she died before they could get her to hospital.

"Despite immediate efforts to revive her, she died at the scene," said police from the canton of Valais.

Police have launched an investigation to determine the cause of the tragedy.

Balet had recently won the Freeride World Tour for the second time. She was the youngest participant ever to win the extreme snowboarding competition.

"Estelle Balet was a naturally gifted shining star and demonstrated remarkable talent ... bringing home her second title as World Champion just a few weeks ago in Verbier," a statement from the event organisers said.

"I feel a great sadness, a sense of bitterness and above all a solidarity with those close to her," Nicolas Hale-Woods, the Freeride World Tour founder, told AFP. He said it was a reminder that even when supervised, practising freeride snowboarding on a mountain carries "its share of uncertainty."

Balet began snowboarding as a child and was competing in freeride events as a teenager. She also often made films about snowboarding. In an eerie interview with a Swiss TV station she said that when she participates in a snowboard film, she often thinks fearfully of the possibility of an avalanche before she pushes off a lip.