Norway's Alexander Dale Oen, the defending world champion in the 100 breaststroke and a top contender for a gold medal at the London Olympics, was found dead in his bathroom late Monday night.

The 26-year-old, who was training with the Norwegian national team in Arizona, died of cardiac arrest. The country's swimming federation said he was found sprawled on the bathtub. Teammates became worried when repeated knocks on the door went unanswered. A team doctor performed CPR before an ambulance arrived, but the young swimmer was never resuscitated and was pronounced dead at a nearby hospital.

"We're all in shock," Norway coach Petter Loevberg told reporters. "This is an out-of-the-body experience for the whole team over here. Our thoughts primarily go to his family who have lost Alexander way too early."

[Photos: Alexander Dale Oen (1985-2012)]

Even at 26, Dale Oen was already the greatest swimmer in Norwegian history. He won the nation's first swimming medal in Beijing, a silver in the 100 breast. Three years later, he won the same race at the world championships, solidifying himself as a favorite for the upcoming Summer Olympics. It was that race that turned Dale Oen from an athletic star into a national hero.

He led wire-to-wire and won by half a body length over a field that included one of the greatest breaststrokers in history, Kosuke Kitajima. His time of 58.71 narrowly missed the world record in the event. But the athletic achievement was only a small part of the overall meaning.

Dale Oen's victory came three days after the Norwegian massacre that killed 77 people. With the country still reeling from the attacks, Dale Oen's win provided a brief sense of diversion. He dedicated his victory to the victims, pointing to the flag on his cap after touching the wall.

"We need to stay united," he said after the race. "Everyone back home now is of course paralyzed with what happened but it was important for me to symbolize that even though I'm here in China, I'm able to feel the same emotions."

In Beijing, Dale Oen entered the final as the top seed but was defeated in the final 50 meters by Kitajima. He seemed to carry that defeat ever since. Quotes on his personal website and Twitter page often had a theme of redemption. London was supposed to provide it.

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