Ukrainian President Volodymyr Zelensky has condemned a "horrific" Russian ballistic missile attack on the northeastern Ukrainian city of Sumy on Sunday, after repeated warnings from Ukrainian officials that a fresh offensive on the area could be imminent.

Russia has debunked claims by Ukraine that Moscow enlisted an unconfirmed number of Chinese nationals to fight alongside its soldiers on the battlefield. Russian Deputy Foreign Minister Andrey Rudenko,

"Putin was not satisfied with soldiers from North Korea. Now he is trying to cover his shortages by pulling in yet another nation — the Chinese," the president said.

Ukraine's air defenses shot down 56 of 88 Russian drones, its air force said. It added that 24 drones were "lost" as the military used electronic warfare to redirect them.

Russia launched a bevy of drone attacks at Ukraine Saturday, killing one person and injuring several others, coming amid warnings that Moscow is replenishing troops for renewed offensives.

Four people were injured in Russian strikes against Ukraine. Plus, the US special envoy for Ukraine found himself in hot water over comments that appeared to suggest that Ukraine could be divided like post-war Berlin.