PARIS (AP) -- Camille Muffat, the French swimmer who won three medals at the 2012 London Olympics and then retired suddenly two years later, died in a helicopter crash in Argentina. She was 25.
Muffat, who won gold in the 400-meter freestyle in London, was killed when two helicopters filming a reality show crashed Monday in a remote area about 730 miles (1.170 kms) northwest of Buenos Aires.
After years spent in the daunting shadow of Laure Manaudou, Muffat made her breakthrough in London, becoming the fourth French swimmer to win a gold medal at the Olympics after Jean Boiteux, Manaudou and Alain Bernard.
Muffat also won silver in the 200-meter freestyle and bronze in the 4x200 freestyle relay to become only the third Frenchwoman to win three medals at the same Olympics.
Muffat first attracted media attention when she defeated Manaudou in the 200-meter medley at the 2005 French championships, when she was just 15.
"Beyond our sporting rivalries, I had a deep respect for Camille and a true bond that related to our crossed career paths and common shyness," Manaudou said Tuesday. "This morning I'm sobbing over the death of a great champion and a friend."
American swimmer Allison Schmitt, who won the silver medal behind Muffat in the 400 freestyle in London by a mere 0.32 seconds, was among the many athletes who joined in tributes to the French champion.
"Deeply saddened by the sudden death of Camille Muffat. A great racer and champion. My thoughts and prayers are with you all," Schmitt wrote on Twitter.
Britain's Rebecca Adlington, who finished third in the race, also took to Twitter to express her feelings.
"So sad and shocked to wake up to hear the tragic death of Camille Muffat," Adlington wrote. "She was an amazing sportswoman, competitor and lovely person. ... RIP Olympic Champion Camille Muffat. You will be dearly missed."
Muffat, who was also a four-time world championship bronze medalist, retired from swimming last year after ruling out her chances of success at the 2016 Rio Olympics following a dispute with her coach, Fabrice Pellerin.
"Camille, we often called her Mrs. 100 percent," said Muffat's boyfriend, William Forgues. "She succeeded in many things. Let's say nearly everything, But in any case, she was very happy when she left."
On March 6, Muffat posted a final message on her Facebook page from Argentina, writing under a selfie showing her in a dark parka: "All good with me, leaving Ushuaia this morning, see you soon."
Muffat was treated to a rapturous welcome after the London Games. She was paraded in the streets of her home city of Nice and was also made knight of the Legion d'honneur, France's highest decoration.
Olympic gold medalist Amaury Leveaux remembered Muffat as a discrete athlete "who was always there when it was time for a bit of a laugh."
Richard Papazian, the president of the Nice swimming club in southern France where Muffat used to swim, was overcome by emotion.
"I could not believe it and then the news was confirmed. What a terrible tragedy," said Papazia, his voice cracking. "I had a lot of affection for Camille. I can't find the words. It's a terrible destiny."
World swimming's governing body mourned the loss of "one of the most well-known and admired sports persons in her country."
"Muffat was a talented swimmer and a human being of great value. She was and will remain a role model for the youth in France and a true inspiration for all those aiming at becoming successful swimmers," FINA president Julio C. Maglione said in a statement.
AP Sports Writers Jerome Pugmire and Paul Newberry contributed to this report.