Ukraine has pounded targets across Russia with at least 25 drones and nine rockets, in a sweeping attack that one official said had triggered a fire at a major Russian refinery.

Russia and Ukraine have both used drones to strike critical infrastructure, military installations and troop concentrations in their more than two-year war, with Kyiv hitting Russian refineries and energy facilities in recent months.

Russia’s defence ministry said it had downed 25 Ukrainian drones over Russian regions including Moscow, Leningrad, Belgorod, Kursk, Bryansk, Tula and Oryol.

Russian officials reported attacks on a slew of energy facilities, including a fire at Lukoil’s NORSI refinery and a drone destroyed on the outskirts of the town of Kirishi, home to Russia’s second largest oil refinery.

Gleb Nikitin, governor of the Nizhny Novgorod region, posted a picture of the NORSI refinery and said emergency services were working to put out a fire there.

“A fuel and energy complex facility was attacked by unmanned aerial vehicles,” Nikitin said on Telegram.

Russian Telegram channels said a crude distillation unit at the refinery had been damaged and was on fire.

The NORSI refinery can process about 17 million metric tons of oil per year, or 340,000 barrels per day. It typically produces 11 per cent of Russia’s petrol.

Domestic petrol prices are sensitive for motorists and farmers in the world’s biggest wheat exporter ahead of a March 15-17 presidential election. Russia imposed a six-month ban on petrol exports on March 1.

The Baza Telegram channel, which is close to Russian law enforcement, said Lukoil’s Nizhny Novgorod refinery had also been hit, and showed pictures of a plume of black smoke rising into the air and a major fire.

Reuters could not independently verify the report.

Russia’s defence ministry said Ukraine had fired eight RM-70 rockets and one Tochka-U missile at the Belgorod region, where some Russian war correspondents said there had also been an attempt by armed groups to cross into Russian territory.

At least two Ukraine-based armed groups purporting to be made up of Russians opposed to the Kremlin said on their social media pages they had launched an incursion across the Russian border on Tuesday. Reuters could not independently verify the claims.

Oryol region’s Governor Andrei Klychkov said Ukraine had launched a drone attack at a fuel facility in the region, with the RIA news agency citing emergency services as saying one petroleum tank was on fire following the attack.

The governor later said firefighters, who were shown spraying plumes of foam, had put out the fire at an oil storage facility in the region.

At least 17 people from high-rise buildings near the site where the drone crashed were reported to have been evacuated to a temporary accommodation centre.

Officials in several regions continued to report drone attacks after the defence ministry statement. No casualties were reported in the attacks.

One drone flying towards Moscow had been downed over the Ramensky district near the capital, Moscow Mayor Sergei Sobyanin said on Telegram.

-Reuters