South Korea’s spy agency estimates 4,700 North Korean casualties in Russia’s war in Ukraine

South Korea’s National Intelligence Service (NIS) reported that approximately 15,000 North Korean troops were deployed to support Russia’s war in Ukraine on two separate occasions. Of those, an estimated 4,700 soldiers were killed or injured, including about 600 confirmed deaths, lawmakers briefed on the intelligence said on April 30.

According to NIS Director Cho Tae-yong, the agency provided the update during a closed-door session of the National Assembly’s Intelligence Committee. Lawmakers Lee Seong-kweun of the People Power Party and Kim Byung-kee of the Democratic Party relayed the findings to the press after the meeting.

Roughly 2,000 injured soldiers have been repatriated to North Korea by train or plane as of March. Many are under quarantine in locations such as Pyongyang, while deceased personnel were reportedly cremated in Kursk before their remains were returned.

Combat Activity Focused in Kursk

The NIS believes North Korean troops played a key role in Russia’s efforts to retake Kursk, a southwestern Russian city that had been temporarily seized by Ukrainian forces in August last year. Russia reclaimed the territory in March, leading to a decline in active combat.

“Fighting has decreased significantly since March,” said Rep. Lee. “There’s no current evidence of a third deployment, but the possibility remains.”

Rep. Lee noted that North Korean troops have improved their combat capabilities and familiarity with modern weaponry. However, extended deployment has led to issues of discipline, including alcohol abuse and theft.

Political Implications of North Korean POWs

The NIS interprets Russia’s rare acknowledgment of North Korea’s military role as part of a strategic exchange between Kim Jong-un and President Vladimir Putin—a move to bolster postwar alliances while presenting the conflict as a “holy war.”

Two North Korean soldiers captured by Ukrainian forces remain in custody. While South Korea is prepared to offer protection should they request asylum, officials say the soldiers have not expressed a clear intent to defect. North Korea, now officially seen as a combatant party, is reportedly seeking their return, complicating the situation.

In exchange for troop deployments, North Korea is believed to have received military technology and hardware, including drones, electronic warfare systems, and SA-22 missile units, as well as satellite reconnaissance support, according to Rep. Kim.

The two countries are also reportedly working to modernize 14 industrial sectors, spanning metals, aerospace, energy, and tourism. Around 15,000 North Korean laborers have been sent to Russia under these agreements.

Continued Nuclear and Cyber Activity

The NIS also shared updates on North Korea’s internal military activity. Weapons-grade plutonium production continues at the Yongbyon facility, and tunnels at Punggye-ri remain active, enabling a nuclear test at any time if ordered by Kim Jong-un.

North Korea’s cyber operations have grown more sophisticated, utilizing QR code-based phishing (“Q-shing”) attacks, with increased collaboration with Russia. Since 2016, the regime has allegedly stolen 6 trillion won ($4.22 billion) in cryptocurrency from global targets.

Rep. Lee reported that Kim Jong-un remains in good health, actively engaged in national defense and internal governance. He is currently focused on preparations for the 80th anniversary of the Workers’ Party of Korea, the Ninth Party Congress, and managing evolving ties with Russia while anticipating a possible second Trump administration.

North Korea is expected to intensify internal messaging and policy momentum through political events such as Secretariat and People’s Committee meetings.

Chinese Espionage Concerns

Separately, the NIS disclosed 11 incidents since June 2024 involving Chinese nationals photographing South Korean military sites. Targets included airports, ports, NIS buildings, and military bases, with one incident involving a drone filming an aircraft carrier in Busan.

Most suspects were temporary visitors or students, including minors. While the stated intent was travel documentation, officials noted they deliberately avoided legal boundaries by staying outside security perimeters.

“We must update espionage laws to apply not only to North Koreans but also foreign nationals attempting to access or leak state secrets,” said Rep. Lee.

BY KIM JEONG-JAE  [shin.minhee@joongang.co.kr]