Kitefoiler James Jackson Rice, who was gearing up to represent Tonga at the Paris Olympics, has died aged 18.
The athlete, who was known as JJ Rice, died on Saturday while free diving in Faleloa, on the island of Ha’apai in the Tonga archipelago.
His father Darren Rice confirmed his son’s death to local news outlet the Matangi Tonga newspaper.
He said Mr Rice died after a suspected blackout in shallow water. His body was found on the seafloor underneath the boat at about 12.15pm by other divers.
Efforts to resuscitate him had failed, the newspaper reported.
The kitefoiler was set to become the first Caucasian to represent Tonga at an Olympic Games.
He earned his place on the Olympic squad after finishing eighth at the Sail Sydney event in December.
The sport is one of two new sailing disciplines set to debut at the Paris games and involves riders ‘fly’ above the water on hydrofoils attached to boards and powered by huge kites.
They can reach speeds of up to 51mph, according to the Royal Yachting Association.
‘Most amazing brother’
Rice was born in the US to British-born parents but grew up on Ha’apai where his parents operate a tourist lodge.
He represented Tonga in several major sailing competitions, including the Formula Kite World Championships and the World Sailing Championships.
He had recently been training and competing in Europe.
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Paying tribute on social media, his sister Lily described her brother as an “amazing kitefoiler”.
“I was blessed with the most amazing brother in the whole world and it pains me to say that he’s passed away,” she said in a Facebook post.
“He was an amazing kitefoiler and he would have made it to the Olympics and come out with a big shiny medal. He made so many amazing friends all over the world.”
The Paris Olympics take place between 26 July and 11 August.