After a battle in Russia's snowy western region of Kursk this week, Ukrainian special forces scoured the bodies of more than a dozen slain North Korean enemy soldiers.

Among them, they found one still alive. But as they approached, he detonated a grenade, blowing himself up, according to a description of the fighting posted on social media by Ukraine's Special Operations Forces on Monday.

The forces said their soldiers escaped the blast uninjured. Reuters could not verify the incident.

But it is among mounting evidence from the battlefield, intelligence reports and testimonies of defectors that some North Korean soldiers are resorting to extreme measures as they support Russia's three-year war with Ukraine.