According to reports this is the first known combat by North Korean soldiers in Russia's war against Ukraine.

Summary

North Korean soldiers have reportedly engaged in combat with Ukrainian forces in Russia’s Kursk region, marking the first known combat involving these units.

South Korea and the EU have expressed concerns about North Korea’s reported troop dispatch to Russia, while the US and UK have noted potential challenges faced by North Korean troops due to differences in language, culture, and military practices likely to impair joint operations, despite training efforts in Russian facilities.