KYIV, Ukraine (AFP) — More than a million Ukrainians were left without power in freezing cold temperatures on Thursday after a massive nationwide Russian missile and drone attack.

The combined missile and drone attack, launched in waves throughout the early hours of Thursday, knocked out electricity for more than a million subscribers in Ukraine’s west, hundreds of kilometers from the front lines.

“As of now, 523,000 subscribers in Lviv region are without electricity,” regional head Maksym Kozytskyi said on social media.

Regional officials said at least another 280,000 were cut off in the western Rivne region and another 215,000 in the northwestern Volyn region, which also borders Poland.

The full extent of the damage was still being assessed on Thursday morning, with Russian drones also having targeted the capital Kviv, the northeastern city of Kharkiv and port city of Odesa on the Black Sea and other regions reporting power outages.

“Power engineers are working to ensure backup power supply schemes where possible. They have already started restoration work where the security situation allows,” the energy ministry said.

A senior United Nations official, Rosemary DiCarlo, this month warned Russian attacks on Ukraine’s energy infrastructure may make this winter the “harshest since the start of the war.”

Russia’s defense ministry also said Thursday it had downed 25 Ukrainian drones fired overnight, including 14 over the southern Krasnodar territory -- just to the east of the annexed Crimean peninsula.