WASHINGTON — Defense Secretary Lloyd Austin said Wednesday that North Korean troops wearing Russian uniforms and carrying Russian equipment are moving into the Kursk region near Ukraine in what he called a dangerous and destabilizing move.

Austin spoke at a news conference with South Korean Defense Minister Kim Yong-hyun as concerns grow over Pyongyang’s deployment of up to 11,000 troops to Russia.

He said officials are discussing what to do about the deployment.

Austin said the U.S. remains concerned that Russia will use North Korean troops in combat, but “whether they will be engaged in combat remains to be seen.”

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Kim said he did not necessarily believe the deployment would spark war on the peninsula, but could increase security threats between the two nations. There is a “probability” that Pyongyang would demand higher technologies in exchange for deploying its troops, such as nuclear and ballistic missile capabilities, he said, speaking through an interpreter.

Seoul and its allies estimate that the number of North Korean troops now sent to Russia has risen to 11,000, according to a senior South Korean presidential official, who spoke on condition of anonymity during a background briefing. More than 3,000 of them are believed to have moved to battle zones in western Russia, the official said, without specifying locations.

Some North Korean advance units of these troops have already arrived in Kursk, where Ukraine successfully held territory after a surprise counter-incursion in August.

The video in the player above is from a previous report.