Pentagon spokeswoman Sabrina Singh says North Korea has sent about 10,000 troops to Russia to train and fight in Ukraine within "the next several weeks." Singh said Monday that some of those soldiers have already moved closer to Ukraine. She says the U.S. is "increasingly concerned that Russia intends to use these soldiers in combat or to support combat operations against Ukrainian forces in Russia's Kursk" region. It comes after NATO said some of the North Korean troops have already been deployed in the Kursk border region, where Russia has been struggling to push back a Ukrainian incursion.