North Korean troops have not been seen on the frontlines in Russia’s Kursk region for several weeks, a Ukrainian military official said Friday, amid reports of mass casualties among Pyongyang’s forces.

North Korea sent its best troops to aid Russia in its war against Ukraine. But after months of suffering severe losses, they have been taken off the front line.

Ukrainian special forces tell the BBC they have not seen any North Koreans in Russia's Kursk region in three weeks.