VILLA CASTELLI, Argentina (AP) Investigators picked through the wreckage of two helicopters Tuesday, removing cellphones, bits of paper and other charred and unrecognizable items, as France mourned the loss of prominent athletes in the dual crash in the Andean foothills.
The eight French nationals and two Argentine pilots on the two aircraft were killed when they collided and burst into flames shortly after taking off Monday near the remote settlement of Villa Castelli in northwestern Argentina.
Among the victims were Olympic champion swimmer Camille Muffat, Olympic bronze-medalist boxer Alexis Vastine and pioneering sailor Florence Arthaud. They were contestants on the reality TV show ''Dropped,'' which was being shot in the sparsely populated region.
Expressions of grief poured in from French athletes and officials, including President Francois Holland, who said he felt ''immense sadness.'' The International Olympic Committee announced it would fly its flag at half-staff for three days.
French officials said they would work with Argentine investigators to determine the cause of the accident.
La Rioja's aviation director, Daniel Gorkich, told The Associated Press that both pilots were highly trained and he speculated that afternoon sun and strong winds might have been a factor.
At the moment of impact ''the sun was setting on the Andes mountain range directly in front of them. Also this is an area with wind gusts,'' Gorkich said.
A widely circulated video shows the blades of one helicopter hitting the rails of the second, causing both aircraft to lose control and crash.
The two Eurocopters crashed about 50 feet (15 meters) apart and were destroyed. One aircraft was so charred that only the blades were recognizable.
Fabrice Pellerin, Muffat's former coach, fondly recalled the 25-year-old swimmer who won gold in the 400-meter freestyle as well as a silver and a bronze at the 2012 London Olympics. ''Always smiling. She was a fantastic person,'' he said.
Vastine's death was a terrible loss, said Dominique Nato, the former technical director of the French Boxing Federation. ''It feels like I've lost a member of my family. He was my friend, he was like my little brother.''
Vastine, 28, won a bronze medal at the 2008 Olympic Games in Beijing, lost in the quarterfinals four years later in London and was looking to compete again at the Olympics next year in Rio de Janeiro.
Arthaud, 57, was perhaps the best known, for being a pioneer in sailing. In 1990, she became the first woman to win the famed Route du Rhum race, a trans-Atlantic single-handed yacht race between Brittany and the Caribbean island of Guadeloupe.
''She was a fighter,'' said French sailor Jean-Luc Van Den Heede, who was second in the Route du Rhum race in 1998. ''At the time it was extraordinary because not many women were doing this. She opened the way for others.''
The other French victims were identified as Laurent Sbasnik, Lucie Mei-Dalby, Volodia Guinard, Brice Guilbert and Edouard Gilles. The pilots were Juan Carlos Castillo and Roberto Abate.
The wife of Castillo, Cristina Alvarez, told television station Todo Noticias that her husband was a veteran of the Falklands War in 1982 and had extensive experience flying helicopters, including in challenging places like Antarctica.
Her voice cracking, she said her husband was ''extremely happy'' because he had recently found out he was going to be a grandfather.
The crew for ''Dropped'' arrived Sunday in Villa Castelli, where it had previously filmed a version of the reality show for Switzerland and Denmark, Mayor Andres Navarrete said.
The crash was one the deadliest incidents yet related to reality TV shows, some of which involve taking celebrities and others to far-flung places to face challenges both physical and mental.
''Dropped'' was being carried by TF1, which is France's leading private-sector network. It canceled another reality show two years ago after a 25-year-old participant died of a heart attack on the first day of filming in Cambodia.
The Adventure Line Productions company was behind both programs. In a statement, it said its staffers were ''devastated'' by the helicopter accident and ''share the deep pain of the families and loved ones.''
Reality TV shows can appeal to former adrenaline-powered star athletes who are looking for new challenges or fun.
William Forgues, Muffat's companion, told i-Tele cable news channel that Muffat had been instructed not to reveal details about the show's filming.
But she ''told everybody that it was great,'' he said. ''She was not forced (to do things). She was where she wanted to be.''
''C'est la vie,'' he added.
Associated Press writers Peter Prengaman, Victor Caivano and Almudena Calatrava in Buenos Aires and Jamey Keaton and Jerome Pugmire in Paris contributed to this report.