MOSCOW: Ukrainian forces fired more than 1,000 drones at Russia overnight, including hundreds launched toward Moscow, officials said Sunday as the Kremlin was wrapping up the third and last day of its parliamentary elections.

Moscow's mayor described the wave of drones as the “largest ever” attack on the Russian capital and said there had been damage to a Moscow oil refinery and a residential building.

Across the wider Moscow region, the attack killed two people and wounded 20, local Gov. Andrei Vorobyov said. The dead were a 74-year-old man and a 44-year-old woman, he said.

There was no immediate comment from Ukraine on the attack.

The voting in Russia was the country's first wartime parliamentary election -- a balloting that was virtually devoid of opposition to President Vladimir Putin's policies and is all but certain to cement the Kremlin's dominance.

Russia also held voting in four Ukrainian regions that Moscow illegally annexed after the war began but still doesn't fully control, and in Crimea, the Black Sea peninsula that was illegally annexed by Russia in 2014. Kyiv has denounced the action as illegal.

Russia's Ministry of Defence said that its forces shot down 1,100 Ukrainian drones across the country, as well as over the annexed Ukrainian peninsula of Crimea and the waters of the Black Sea.

Moscow Mayor Sergei Sobyanin said that 450 drones had been destroyed en route to the Russian capital, and that the attack had damaged the Moscow Oil Refinery and a residential building.

He said the “unprecedented attack” on the capital was an attempt to disrupt the elections.

"The enemy failed in this regard," he said.