A North Korean soldier fighting for Russia has died while in Ukrainian captivity, South Korean intelligence says. The soldier is believed to be one of thousands of North Koreans helping Russia fight its nearly three-year war in Ukraine.

Despite their elite status, North Korea's "Storm" troops were ill-prepared for the war, South Korea's National Intelligence Service said.

South Korea's military has said that North Korea is preparing to continue aiding Russia in its war with Ukraine, despite casualties.