Ukraine has been hit by a surge in Russian ballistic missile attacks, about a third of which used North Korean weapons that can only fly because they run on Western circuitry, obtained despite sanctions,

Russia reportedly provided North Korea with oil, anti-air missiles and economic help in exchange for troops to support Moscow's war on Ukraine.

Technical advisors from North Korea have arrived in Russian-controlled Mariupol, Ukrainian sources told CNN. Soldiers from Kim Jong Un's army were also spotted in Kharkiv. Ukrainian sources told CNN that technical advisors from North Korea have arrived in Mariupol,