Air defences shot down 41 of 48 Russian drones launched from Russia’s western Kursk region and the occupied peninsula of Crimea seized by Moscow in 2014, the air force said. Only Iranian-made “Shahed” drones were used for the attack, it said.

Drone attacks have happened almost nightly for weeks and the latest strike was the largest one so far this month.

The Ukrainian President’s office said people’s homes and commercial buildings were damaged by drone debris in various regions.

Unspecified infrastructure facilities in several regions and a natural gas pipe in the northeast Kharkiv region were damaged, it said in a statement.

There were no immediate reports of casualties.

DTEK, Ukraine’s largest private energy producer, said one of its thermal power stations located in a frontline region in the east was shelled for the sixth time this month.

It said on Telegram messenger that heating to residents was disrupted but did not give a specific number of people affected. Temperatures in Ukraine are well below zero Celsius.

As a second winter of war sets in, Ukrainians fear that Russia plans to target its energy system.

(Reporting by Lidia Kelly in Melbourne and Olena Harmash in Kyiv; Editing by Tom Balmforth)