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Ukraine attacks Rosneft's biggest refinery

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Ukraine sends dozens of drones over Russia - local

officials

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Ukrainian drone downed near Kirishi refinery

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Putin says Ukraine trying to disrupt Russia's election

(Recasts with details of refineries attacked and their

significance)

By Guy Faulconbridge and Lidia Kelly

MOSCOW, March 13 (Reuters) - Ukraine launched a sweeping

drone attack on Russian regions on Wednesday, causing a fire at

Rosneft's biggest oil refinery in what President Vladimir Putin

said was an attempt to disrupt Russia's presidential election.

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.

The day after seriously damaging Lukoil's NORSI

refinery, a Ukrainian drone attacked Rosneft's Ryazan oil

refinery, Russia's seventh largest, 180 km (110 miles) from

Moscow.

Russian media said around 60 drones had been destroyed

over Russian sovereign territory over just several hours.

"The Ryazan oil refinery was attacked by a UAV (unmanned

aerial vehicle)," Pavel Malkov, governor of the Ryazan region

bordering the Moscow region to its north, said on the Telegram

messaging app.

"A fire broke out as a result. According to preliminary

information, there are injuries," he said, without elaborating.

Russia's RIA state news agency said four Ukrainian drones

attacked the plant in the early hours, leading to a 175 sq m

blaze. The fire was put out several hours later. The impact on

its production was not immediately clear.

Unverified video footage posted on social media showed a

plume of black smoke soaring above flames at the Ryazan plant,

which refines about 12.7 million tonnes of oil a year, or 4.6%

of the Russian total, according to industry sources.

REFINERY SECURITY TIGHTENED

It accounts for about 6.4% of Russia's gasoline production,

4.1% of diesel, 7.7% of fuel oil and 8.0% of aviation fuel,

according to the sources. Full Russian production figures are no

longer published.

A drone was destroyed by air defences on its approach to the

Kirishi refinery, Russia's second largest, in the north of

Russia, Alexander Drozdenko, the Leningrad region's governor,

said. There was no impact on the refinery's work, he said.

Security around oil refineries, a key source of Russia's

income, was tightened in some regions, Russian media reported.

More than 30 drones were destroyed in the air over the

Voronezh region that borders Ukraine, Governor Alexander Gusev,

said on Telegram, adding there was only minor damage.

Putin in remarks published on Wednesday accused Kyiv of

attempts to interfere with the March 15-17 presidential election

through its attacks.

"The main goal, I have no doubt about it, is to - if not to

disrupt the presidential elections in Russia - then at least

somehow interfere with the normal process of expressing the will

of citizens," Putin told Russia's RIA state news agency and

Rossiya-1 state television in a wide-ranging interview.

Putin, who launched a full-scale invasion of Ukraine two

years ago, is nearly certain to win the vote.

In the Belgorod region, falling debris from downed drones

damaged a gas supply line and cut off power to some villages.