When Mariia Pankova last exchanged messages with her close friend Pavlo in December, she had no idea that he was among the Ukrainian troops fighting in Russia's Kursk region.

Russian forces claim to have pulled off an audacious operation, using a subterranean pipeline to sneak past Ukrainian defenses. The reported operation coincided with a full-on Kremlin effort to push Kyiv’s forces out of Russia’s Kursk region,

Russian forces have begun an assault on the town of Sudzha, the main population center in the Kursk region that was captured by Ukraine last year, a top Russian commander said on Tuesday. The advance puts Moscow on the verge of ending the first invasion of Russian territory since World War II.