A nighttime missile and drone attack on Ukraine killed at least four people and injured 20 others in Kyiv, city mayor Vitali Klitschko said Friday, as Russia targeted at least six regions across the country with 407 drones and 44 missiles in one of its largest co-ordinated attacks of the three-year war.

Russia's Defence Ministry said on Friday that its forces had carried out a massive and successful strike on military and military-related targets in Ukraine overnight in response to what it called Ukrainian "terrorist acts" against Russia.