Updated

Alexander Dale Oen, a world champion swimmer who was one of Norway's top medal hopes for the London Olympics, has died during training camp in Flagstaff, Ariz. He was 26.

Federation President Per Rune Eknes said Dale Oen died after suffering a cardiac arrest.

In a statement, the federation said the 100-meter breaststroke world champion was found collapsed on the floor of his bathroom late Monday. He was taken to the Flagstaff Medical Center, where he was pronounced dead.

"We're all in shock," Norway Coach Petter Loevberg said. "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."

Hospital spokeswoman Starla Collins confirmed the death, but did not provide further details.

Dale Oen won the 100 breaststroke at the worlds in Shanghai last July and took silver at the 2008 Beijing Olympics.

His triumph in Shanghai came just three days after the massacre in Norway by right-wing extremist Anders Breivik that killed 77 people. He dedicated the win to the victims of that massacre, pointing to the Norwegian flag on his cap after the finish to send a message to his countrymen back home.

"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."

The Norwegian team was holding a camp in Flagstaff ahead of the Olympics. The federation said Dale Oen had only a light training session on Monday and played golf that day. But teammates became worried when the swimmer spent an unusually long time in the shower and entered his bathroom when he failed to respond to their knocks on the door.

The federation said "they found Dale Oen laying partly on the floor, partly on the edge of his bathtub."

Team doctor Ola Roensen said he immediately began performing CPR until an ambulance arrived.

"Everything was done according to procedure, and we tried everything, so it is immensely sad that we were not able to resuscitate him," Roensen said. "It is hard to accept."