An enemy that swarmed the battlefield in large groups while under fire, seemingly oblivious to the dangers of drones and fire from automatic weapons. An elite corps of ghost soldiers who chose suicide over surrender. They fought and died in their thousands, then apparently vanished from the battlefield.

Axar.az reports, citing BBC, North Korea's soldiers were sent to fight by Pyongyang alongside Russian forces as they sought to repel a Ukrainian offensive on Moscow's territory at the end of 2024. They paid a heavy price, as many as 3,000 killed in action from the 13,000 deployed.

Ultimately, they would adapt their tactics, and with Russia would drive Ukrainian forces from its Kursk region. In combat terms, little has been heard of them since, but according to Ukraine's president, Volodymyr Zelensky, North Korean forces, and their weaponry, are soon to make a dramatic return to Russia's war in Ukraine.

Last month, Zelensky warned that up to 50,000 North Koreans will be deployed in Russia, revising an earlier estimate of 30,000 troops. He called on South Korea to provide support for his country's air defence.

But why, after such heavy losses, would North Korea send more men to fight for Russia, and what happened to its soldiers sent in the first place?

"They're still there", said Dr Yang Uk, research fellow at the Asan Institute for Policy Studies, Center for Foreign Policy and National Security in Seoul. "They are defending Russian territory for another counterattack from Ukraine. And we believe that some of the engineer corps or workers might be in [the Russian-occupied] Donbas area but that's not the combat troops."

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