Video: See how three sports stars died in Helicopter Crash

Three French sports personalities are among 10 people killed in a helicopter crash in Argentina, the French presidential office confirmed.

Eight French nationals and their two Argentine pilots died when two helicopters collided in La Rioja province in the country's north-west.

Yachtswoman Florence Arthaud, Olympic swimmer Camille Muffat and Olympic boxer Alexis Vastine all perished.

Both helicopters were involved in the filming of TV survival show Dropped.

The show, on channel TF1, flies celebrities into rough terrain by helicopter and films their attempts to find food and shelter.

"The sudden death of our fellow French nationals is a cause of immense sadness," said a statement from French President Francois Hollande.

The cause of the crash is as yet unclear and investigations are under way.

Camille Muffat, Alexis Vastine and Florence Arthaud were confirmed dead by President Hollande's office

Camille Muffat, 25, won three medals, including gold in the 400m freestyle in the 2012 London Olympics. She retired from competitive swimming in 2014.

Alexis Vastine, 28, won bronze at the 2008 Beijing Olympics in the light-welterweight category. He was narrowly beaten in the quarter-finals of the 2012 Games.

Florence Arthaud, 57, was a hugely accomplished sailor, winning the 1990 Route du Rhum, the prestigious solo Atlantic race. A serious car accident put her in a coma when she was 17.