North Korea has decided to send a "large-scale" troop deployment to support Moscow's war in Ukraine, with 1,500 special forces already in Russia's Far East and undergoing training, Seoul's spy agency said Friday.
The National Intelligence Service said the North had decided to send thousands of soldiers to help Russia, releasing detailed satellite images it said showed the first deployment.
South Korea's President Yoon Suk Yeol convened an emergency security meeting Friday, with Seoul slamming Pyongyang's move as "a significant security threat not only to our country but also to the international community," the president's office said.
The NIS said it had "detected that from the 8th to the 13th (of October), North Korea transported its special forces to Russia via a Russian Navy transport ship, confirming the start of North Korea's military participation" in Russia's war in Ukraine.
According to the NIS, multiple Russian landing ships and frigates have already completed transporting the first contingent of troops, who are currently stationed in military bases across Russia's Far East.
The special forces soldiers "are expected to be deployed to the front lines (of the Ukraine conflict) as soon as they complete acclimatisation training," it said.
The soldiers have been issued Russian military uniforms and Russian-made weapons, the NIS said.
"This seems to be an effort to disguise the fact that they are North Korean troops by making them appear as Russian soldiers," NIS added.
More troops are likely to be sent soon, NIS said, adding that it estimated the North could send around 12,000 soldiers in total.
"A second transport operation is expected to take place soon," it said.
Pyongyang and Moscow have been allies since North Korea's founding after World War II and have drawn even closer since Russia's 2022 invasion of Ukraine, with Seoul and Washington long claiming that Kim Jong Un has been sending weapons for use in Ukraine.
Russian President Vladimir Putin made a rare visit to Pyongyang in June, with the two countries signing a mutual defence treaty, fuelling speculations of further arms transfers -- which violate rafts of UN sanctions on both countries.
The NIS said Friday that the North had "provided Russia with more than 13,000 containers' worth of artillery shells, missiles, anti-tank rockets and other lethal weapons" since last August.
Ukrainian President Volodymyr Zelensky had flagged Thursday intelligence reports saying North Korea was training 10,000 soldiers to support Russia in its fight against Kyiv.
Zelensky suggested that Russia is relying on North Korean troops to compensate for its substantial losses, as many young Russians seek to avoid conscription.
Earlier this month, Ukrainian media reported that six North Korean military officers were killed in a Ukrainian missile attack on Russian-occupied territory near Donetsk on October 3.
Seoul's defence minister, Kim Yong-hyun, told lawmakers at the time that it was "highly likely" that the report was true.
Experts said that moving from supplying shells to soldiers to Russia was the logical next step.
"For North Korea, which has supplied Russia with many shells and missiles, it's crucial to learn how to handle different weapons and gain real-world combat experience," said Lim Eul-chul, a professor at Seoul's Institute for Far Eastern Studies.
"This might even be a driving factor behind sending North Korean soldiers -- to provide them with diverse experiences and war-time training," he told AFP.
