All North Korean recruits are taught a song that includes a verse about saving their last bullet for themselves to avoid capture, one former soldier told NBC News.

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.

Soldiers from North Korea fighting on behalf of Moscow have reportedly pulled back from the frontline in Russia's Kursk region.