Norwegian world champion swimmer Alexander Dale Oen has died of cardiac arrest while training in he southwestern U.S. state of Arizona. The 26-year-old was in the city of Flagstaff preparing to compete in this summer's Olympics in London.

The Norwegian Swimming Federation said Dale Oen was found on a shower-room floor at the training facility late Monday.

Norwegian Olympic Hopeful Dies Suddenly

Norway Swimming Coach Petter Loevberg told the Associated Press, "We are all in shock," describing the immense grief as an "out-of-body experience."

Norwegian Olympic Hopeful Dies Suddenly

Dale Oen won the 100-meter breaststroke at the World Championships in Shanghai last July, just days after the killing of 77 people by confessed right-wing killer Anders Behring Breivik in Oslo and the island of Utoya. The swimmer dedicated his win to the victims of the massacre.

Norwegian Olympic Hopeful Dies Suddenly

Dale Oen won a silver medal at the 2008 Beijing Olympics. He was considered one of Norway's top hopes for a medal at the London games.