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, Reuters reported.

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.

“Self-detonation and suicides: that’s the reality about North Korea,” said Kim, a 32-year-old former North Korean soldier who defected to the South in 2022, requesting he only be identified by his surname due to fears of reprisals against his family left in the North.

“These soldiers who left home for a fight there have been brainwashed and are truly ready to sacrifice themselves for Kim Jong Un,” he added, referring to the reclusive North Korean leader.

Kim, introduced to Reuters by Seoul-based human rights group NK Imprisonment Victims’ Family Association, said he had worked for North Korea’s military in Russia for about seven years up until 2021 on construction projects to earn foreign currency for the regime.

Ukrainian and Western assessments say Pyongyang has deployed some 11,000 soldiers to support Moscow’s forces in Russia’s western Kursk region, which Ukraine seized in a surprise incursion last year. More than 3,000 have been killed or injured, according to Kyiv.

North Korea’s mission to the United Nations in Geneva did not immediately respond to a request for comment.

Moscow and Pyongyang initially dismissed reports about the North’s troop deployment as “fake news”. But Russian president Vladimir Putin in October did not deny that North Korean soldiers were currently in Russia and a North Korean official said any such deployment would be lawful, read the report.

Ukraine this week released videos of what it said were two captured North Korean soldiers. One of the soldiers expressed a desire to stay in Ukraine, and the other to return to North Korea, Ukrainian President Volodymyr Zelenskiy said.

North Korea’s deployment to Russia is its first major involvement in a war since the 1950-53 Korean War. North Korea reportedly sent a much smaller contingent to the Vietnam War and to the civil conflict in Syria.

The United States has warned the experience in Russia will make North Korea “more capable of waging war against its neighbours”.

North Korea’s leader Kim has previously hailed his army as “the strongest in the world”, according to state media. Propaganda videos released by the regime in 2023 showed bare-chested soldiers running across snowy fields, jumping into frozen lakes and punching blocks of ice for winter training.

But a South Korean lawmaker briefed by the country’s spy agency on Monday said that the numbers of North Korean soldiers wounded and killed on the battlefield suggests they are unprepared for modern warfare, such as drone attacks, and may be being used as “cannon fodder” by Russia, Reuters reported.

More worryingly there are signs these troops have been instructed to commit suicide, he said.

“Recently, it has been confirmed that a North Korean soldier was in danger of being captured by the Ukrainian military, so he shouted for General Kim Jong Un and pulled out a grenade to try to blow himself up, but was killed,” Lee Seong-kweun, who sits on the South Korean parliament’s intelligence committee, said.

Memos carried by slain North Korean soldiers also show that North Korean authorities emphasized self-destruction and suicide before capture, he added.

When asked about further details of the cases he referred to, he declined to elaborate saying it was information from Ukraine shared with South Korea’s National Intelligence Service (NIS). NIS did not answer calls seeking comment on Tuesday.

Suicides by soldiers or spies not only show loyalty to the Kim Jong Un regime but are also a way to protect their families left at home, Yang Uk, a defence analyst at the Asan Institute of Policy Studies said.

Ukraine’s Zelenskiy said on Sunday Kyiv is ready to hand over captured North Korean soldiers to their leader Kim Jong Un if he can facilitate their exchange for Ukrainians held captive in Russia.

For some North Korean soldiers, however, being captured and sent back to Pyongyang would be seen as a fate worse than death, said Kim, the North Korean defector and former soldier.

“Becoming a prisoner of war means treason. Being captured means you are a traitor. Leave one last bullet, that’s what we are talking about in the military,” he said.