A North Korean missile unit has deployed inside Russia to support Moscow's war against Ukraine, marking what Reuters described as Pyongyang's most significant involvement in a war since the 1950s, as a North Korean-made ballistic missile killed at least five members of one family when it struck a residential home in central Ukraine last week, the first confirmed use of a North Korean missile in the war since August 2025. Russia and North Korea jointly confirmed the deployment in April 2025, with Moscow's top military commander praising North Korean forces' role after Russia said it had retaken Kursk territory, while Pyongyang said the deployment had been personally ordered by leader Kim Jong Un. South Korea's National Intelligence Service has separately estimated North Korean casualties in the Kursk fighting at roughly 6,000 killed or wounded, a figure corroborated by an earlier assessment from the U.K.'s Defense Intelligence agency. HUR said approximately 3,000 North Korean troops with combat experience have already returned home, with most becoming military instructors who pass on lessons from modern, high-intensity warfare to North Korea's broader military. The agency said mastering unmanned drone technology has become one of Pyongyang's primary objectives in supporting the Russian war effort, alongside gaining hands-on experience in contemporary combat operations more broadly.