Australia's double world champion snowboarder Alex Pullin drowned while spear fishing off a Gold Coast beach on Wednesday.
A police spokesperson said a 32-year-old man, later identified as Pullin, was unresponsive when taken from the water and died despite receiving CPR from lifeguards and emergency treatment from paramedics.
The accident happened at Palm Beach around 10.40am local time. Pullin had been diving on an artificial reef when he was found by a snorkeler.
Pullin, known by the nickname "Chumpy", won gold medals in the snowboard cross event at the 2011 La Molina and 2013 Stoneham World Championships. He was Australia's flag bearer at the 2014 Sochi Winter Olympics.
Australia's winter sports body Snow Australia said it was shocked and saddened by Pullin's death.
"Our deepest condolences are with Alex's family, as well as his team-mates and support staff," Snow Australia said in a statement. "Alex was a beloved member of the Snow Australia community and he will be dearly missed."