Katherine Díaz Hernández reportedly paddled out into the water to hug a friend when she was struck by lightning and killed in El Salvador.
The 22-year-old, who was hoping to qualify for the Tokyo Olympics later this year, was training near her home at the Pacific coast beach of El Tunco when the freak tragedy occurred.
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Diaz was brought to shore by onlookers, however she couldn't be revived.
Her uncle has since revealed that she had gone to hug a friend when she was struck.
"Katherine came over to hug her, as soon as she finished hugging her, the noise was heard," Beto Diaz, who was in the water, told a newspaper in El Salvador.
"She, the friend, was thrown by the force of the lightning strike too, the board threw me back.
"Katherine died instantly."
Diaz had been training for a global tournament, set to be held in El Salvador, that serves as a qualifying even for this year's Summer Olympic Games.
Surfers in El Salvador are planning to hold a “paddle out” on Tuesday to remember one of the country's top surfers.
Surfers usually sit atop their boards at a distance from shore at paddle outs, and in this case they plan to share memories of Díaz, who participated in international competitions.
Surfing world in shock over Katherine Diaz's death
"Katherine was a girl very passionate about sports, she was very motivated and happy for the event that was approaching," the country's surfing federation (FESASURF) said in a statement.
El Salvador's National Institute for Sport (INDES) said: "We raise a prayer for the eternal rest of her soul and we express our most sincere condolences to her family."
The International Surfing Association added: "Katherine embodied the joy and energy that make surfing so special and dear to us all, as a global ambassador of the sport.
"She excelled at the international competition level, representing her country with pride at both the ISA World Surfing Games and ISA World Junior Surfing Championship.
"We send our heartfelt condolences to Katherine's family, the surfers of El Salvador, and to all those in the international surfing community whose lives she touched."
Diaz started surfing at the age of nine, and was also well known in El Tunco for her skills as a chef.
Yamil Bukele, the president of the Salvadoran Sports Institute, wrote: “I greatly regret this death, and I join in the family's pain.”
Her brother Bamba Diaz has also posted several tributes.
“Sister we will always carry you in our hearts,” he wrote.
“God decided to take you now. We already miss you. Love forever.”
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