Kazakh figure skater Denis Ten, who won bronze at the Sochi Olympics in 2014, died on Saturday aged 25 after being stabbed, Kazakhstan’s culture and sports ministry announced. Ten died in hospital after medics fought to save his life following the attack in which he lost three litres of blood, the ministry’s press service said.

Kazakhstan’s Vesti.kz news website reported that Ten died of stab wounds after being attacked by car thieves. He was reportedly stabbed in the right thigh, causing severe blood loss. City police said that he was stabbed by two unidentified attackers who were trying to steal mirrors from his car, RIA Novosti news agency reported.

The International Skating Union said in a tweet it was “deeply saddened” by the news. “Our heartfelt condolences go out to Denis’ family, friends and fans across the world,” it said. Social media erupted in sorrow and anger at the news of his death amid demands for an investigation.

Ten was of Korean origin and his great-great-grandfather was a Korean-born independence fighter, General Min Keung Ho. He was trained by American coach Frank Carroll following a spell with Russia’s most renowned coach, Tatiana Tarasova.

Tarasova told RIA Novosti news agency in Russia that she had spoken to his mother while he was still alive in hospital. “What a nightmare. What a tragedy!” she said. Ten won silver at the World Figure Skating Championships in 2013 and bronze in 2015. He won the 2015 Four Continents title in Seoul. “I am ethnically Korean and I am virtually skating in my home country,” he said at the time.

At Sochi in 2014, he won bronze in the men’s free skating final, despite skating in two different boots.