The Kremlin on Thursday accused Ukrainian saboteurs of crossing into western Russia and firing on villagers. Ukraine denied the claim and warned that Moscow could use the allegations to justify stepping up its own attacks in the ongoing war. The exact circumstances of the alleged attack reported in the Bryansk region were unclear, including what the strategic purpose of such an assault might be. If confirmed, it would be another indication following drone attacks earlier this week that Kyiv may be stepping up pressure against Moscow by exposing Russian defensive weaknesses, embarrassing the Kremlin and sowing unease among Russian civilians....