A “massive” Russian missile and drone attack has targeted power infrastructure across Ukraine, the country’s energy minister German Galushchenko has said.
It is the largest such assault since early September, with reports of several explosions across Ukraine, according to authorities and local media.
Poland, Ukraine's neighbour to the west, scrambled fighter jets to patrol its own airspace as a security precaution, Poland's Operational Command said.
In a statement on social media, Mr Galushchenko said that "a massive attack on our energy system is ongoing" and that Russian forces were "attacking electricity generation and transmission facilities".