Updated

The Japanese swimming federation is reconsidering plans to conduct altitude training following the death of Norwegian 100-meter breaststroke world champion Alexander Dale Oen.

Dale Oen died Monday from cardiac arrest during a pre-Olympic training camp in Flagstaff, Ariz.

Japan's federation was planning to send several London medal hopefuls to train at high altitude in June before the Olympics.

Japanese federation official Koji Ueno said "under the circumstances, we can't send our athletes who feel uneasy about what has happened."

The Norwegian team was holding a camp at elevation in Flagstaff before the Olympics. The federation said the 26-year-old Dale Oen had gone through only a light training session on Monday.

An autopsy was performed Tuesday, but the results were not immediately released.