The US called the move very serious and warned those forces will be “fair game” if they go into combat in Ukraine.

South Korean president Yoon Suk Yeol has vowed he “won’t sit idle” over reports that North Korea has sent thousands of troops to Russia to aid Vladimir Putin’s invasion of Ukraine.

Disguised as Buryats and Yakuts, ethnic minorities from Siberia who have made up a disproportionate share of Moscow’s forces, ...

The U.S. said Wednesday that 3,000 North Korean troops have been deployed to Russia and are training at several locations, ...