French Olympic swimmer Camille Muffat and Olympic boxer Alexis Vastine were among 10 people who died in a helicopter crash in Argentina while shooting a survival TV show.
Yachtswoman Florence Arthaud also lost her life when two helicopters collided in La Rioja province during filming for Dropped.
The French presidential office has confirmed that eight nationals and two Argentine pilots died while filming the reality TV show, which involves celebrities hunting for food and shelter.
French president Francois Hollande said in a statement: "The sudden death of our fellow French nationals is a cause of immense sadness."
Muffat, 25, retired from competitive swimming last year after winning Olympic gold in the 400m freestyle at London 2012, while 28-year-old Vastine clinched boxing bronze at the Beijing Games in 2008.
Arthaud had many achievements in her sailing career, one of which was winning the Route du Rhum in 1990.