North Korea has not responded to reports of its troops captured or killed by Ukraine forces. It has never publicised the deployment or large shipments of North Korean artillery shells and other weapons sent to Russia to help its war against Ukraine, although they marked the country’s first intervention in a major armed conflict overseas in decades.

North Korean troops, unacknowledged by their own country, are getting chewed up in a vicious war in which, far from home, they are “cannon fodder” fighting anonymously on behalf of the Russians.

South Korea's military said on Friday that it suspects North Korea is preparing to send more troops to Russia to fight Ukrainian forces, even after suffering losses and seeing some of its soldiers captured.

Ukrainian special operations forces have given an insight into the brutal, near-suicidal tactics of the North Koreans they have faced in intense fighting in the Russian border region of Kursk.