An unnamed American official reportedly told the British newspaper the Guardian on Tuesday that communist North Korea has documented hundreds of casualties in the Russian invasion of Ukraine.

That estimate is potentially higher than the “dozens” that White House National Security Communications Advisor John Kirby offered on Monday and suggests a massive deployment of force by Pyongyang onto the European border. American and other Western officials, including Ukrainians, believe most of these soldiers are operating in the area around Kursk, a Russian region Ukraine invaded in August in a surprise operation meant to deter the Russian advance into its territory.

Reports of significant battle losses for North Korea this week accompany a barrage of sensational reports on the situation for North Koreans on the battlefield from the Ukrainian government, which accused Russian soldiers of burning the faces of dead North Koreans to obscure their origin and claimed that a large “friendly fire” incident occurred in which North Koreans killed several Russian soldiers.

North Korea has not at press time confirmed the deployment of any troops to the Russian war effort, though its state media and its dictator, Kim Jong-un, enthusiastically support the invasion. Russia and North Korea signed a mutual defense agreement in June that many have suggested now required North Korea to participate in defending Russian territory from Ukrainian attack.

The unnamed “senior U.S. military official” speaking to the Guardian described North Korea as suffering “several hundred casualties” since it involved itself in the Russian invasion this fall. Russia initially invaded Ukraine in 2014 but launched a “special operation” to oust President Volodymyr Zelensky in February 2022 that prompted direct Russian military action, rather than attacks by pro-Russian separatist forces.

“Several hundred casualties is our latest estimate that the DPRK [North Korea] has suffered,” the official said, describing casualties as spanning “everything from … light wounds up to being KIA (killed in action).”

The official attributed the high casualty count to the lack of experience among North Korean troops, though he or she also said that “all ranks” of North Korean soldiers were affected.

The Ukrainian government independently suggested on Wednesday that hundreds of North Koreans had died in the war, citing intercepted phone communications in which Russians working at hospitals commented on the high number of apparent North Koreans coming in. According to the Ukrainian state outlet Ukrinform, the intercepted communications included a nurse lamenting to her husband that hundreds from the battle lines were being brought to her hospital in Moscow by train.

The nurse also reportedly complained that her hospital is “freeing up certain wards” for the Koreans, asking if they were “elite.”

Kirby, the top White House official, described North Korea as suffering “significant losses” in remarks to reporters on Monday.

“I don’t know that we have an exact number, but we do believe that they have suffered some significant losses, killed and wounded, but it’s difficult for me to put an actual number on it,” Kirby said. “I would say certainly in the realm of dozens, several dozens.”

Kirby noted that outgoing President Joe Biden recently approved more sanctions on North Korean individuals believed to be helping fund the Russian invasion and warned that American intelligence believes that the North Koreans are being moved “from the second lines on the battlefield to the front lines on the battlefield meant to be actively engaged in combat operations.”

Separately, at the State Department, spokesman Matthew Miller told reporters at a briefing that American authorities have “seen North Korean soldiers who have been killed in action on the battlefield inside Russia, and if they were to cross the border into Ukraine, that would be yet another escalation by the government of Russia.”

“In our view, the North Korean soldiers who were deployed to Kursk are already legitimate targets. They entered a war, and they are as such combatants that are legitimate targets for the Ukrainian military,” he added.

North Korea and Russia have historically maintained friendly relations that Kim Jong-un and strongman Vladimir Putin have significantly strengthened in the past year, at the apparent expense of North Korea’s closest ally China. Putin visited Pyongyang for the first time in 20 years in June, signing a mutual defense agreement that requires both countries to offer military support in defense of the other. The reports of North Korean troop deployments to the Ukrainian border followed shortly thereafter.

Ukrainian officials have insisted since November that they have seen North Koreans on the front lines. They also claim that Russia is attempting to obscure their presence; neither Russia nor North Korea have confirmed the presence of Kim’s troops in the war theater.

On Monday, President Zelensky published a video on social media he claimed showed Russian soldiers trying “to literally burn the faces of North Korean soldiers killed in battle.”

[Warning: graphic video]

“This is a demonstration of disrespect, which is currently prevalent in Russia, a disrespect to everything human,” Zelensky said in an accompanying social media post. “There is not a single reason for North Koreans to fight and die for Putin. And even after they do, Russia has only humiliation for them.”

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