SEOUL, April 30, 2025 (BSS/AFP) - Around 600 North Korean soldiers fighting for Russia against Ukraine have been killed and thousands more wounded, a Seoul lawmaker said Wednesday, after Pyongyang officially confirmed deploying troops to aid Moscow.

"So far, North Korean troop casualties are estimated at around 4,700, including approximately 600 deaths," MP Lee Seong-kweun, a member of parliament's intelligence committee, told reporters after a briefing by the country's spy agency.

North Korea confirmed for the first time Monday that it had deployed troops to Russia, with state news agency KCNA reporting Pyongyang's soldiers helped Moscow reclaim territory under Ukrainian control in the Russian border region of Kursk.

Moscow had separately confirmed the North's participation, after months of official silence from both countries, even as Seoul and Washington accused Pyongyang of sending ever more troops and weapons to help.

Some 2,000 soldiers have been taken back to nuclear-armed North Korea this year, Lee said, and were now reportedly being held in isolation in Pyongyang and at other locations across the country.

"It is understood that the bodies of fallen soldiers were cremated locally in Kursk before being transported," back to the North, he added.

North Korea "supported Russia's recapture of Kursk by deploying 18,000 troops in two phases," Lee said, adding that the number of clashes in the area had decreased since around March.

Since then, "there have been reports of misconduct within North Korean forces, including excessive drinking and theft," he said.

- Combat capability 'significantly improved' -

South Korea has repeatedly slammed the troop deployment, and criticised the North for sending container-loads of weapons, including missiles, to aid Russia's war against Ukraine.

The nuclear-armed North has received significant technical support from Russia in return, Seoul claimed.

In addition, after six months of fighting, Seoul's National Intelligence Service estimates that the North Korean forces' "combat capability has significantly improved," Lee said.

"Early inexperience has diminished and they have become more proficient in using new weapon systems, including drones," he said.

Lee said it was not possible to "entirely rule out" that the North could send more soldiers to Russia.

The troops sent to Russia, reportedly from North Korea's elite Storm Corps, have been ordered to kill themselves rather than be taken prisoner, Seoul has previously said.

Moscow and Pyongyang have boosted their military cooperation since Russia launched its 2022 invasion of Ukraine.

The two countries signed a sweeping military deal last year, including a mutual defence clause, when Russian President Vladimir Putin made a rare visit to North Korea.

Pyongyang launched a flurry of ballistic missiles last year in violation of UN sanctions.

Experts have warned that the nuclear-armed North may be testing weapons for export to Russia for use against Ukraine.