A nuclear power plant was among the targets of a massive Ukrainian drone attack against Russian oil and power facilities, Russian officials and media outlets reported on Wednesday.

Air defence systems destroyed a drone attempting to strike a nuclear power facility in the western region of Smolensk bordering Belarus, Governor Vasily Anokhin said on the Telegram messaging app.

The Smolensk Nuclear Power Plant, the largest power generating plant in Russia's northwest, was working normally, RIA state news agency reported, citing the plant's press service.

Reuters could not independently verify the reports and there was no comment from Ukraine.

Russia's defence ministry said on Telegram that 104 drones were involved in raids across western Russia, 11 of which were destroyed over the Smolensk region.

In total, Russian air defences destroyed drones over nine regions, nearly half of them over Kursk, where Russian forces are fighting to drive out Ukrainian troops that have occupied several villages.

Russian petrochemicals giant Sibur said it had temporarily suspended operations at its plant in Kstovo on Wednesday morning after debris from a Ukrainian drone sparked a fire.

There were no casualties at the plant, which is in the Nizhny Novgorod region about 800 km (500 miles) from the Ukrainian border, the company said, adding that emergency services were on site.

One person was injured and hospitalised as a result of a drone attack on the Belgorod region bordering Ukraine, the regional governor said.

Russian aviation watchdog Rosaviatsia temporarily halted flights at the Kazan airport in Russia's Republic of Tatarstan and at the Pulkovo airport in the Leningrad region. Flights have resumed since, according to Rosaviatsia's Telegram statements.

Both sides deny targeting civilians in their attacks in the war that Russia started with a full-scale invasion in February 2022. Kyiv says that its attacks inside Russia aim to destroy infrastructure key to Moscow's war efforts.