Ukrainian drones set fire to Gazprom Neft’s Moscow refinery in Kapotnya overnight into Sept. 20, hitting a facility with capacity to process roughly 11 million metric tons of crude a year. Russia’s Defense Ministry said air defenses downed 1,110 Ukrainian drones across 19 Russian regions and Crimea, the largest overnight total it has reported this year, exceeding August’s high of 822.

Ukraine’s General Staff said the strike damaged the refinery’s AVT-6 primary processing unit, an integrated oil processing unit and an isomerization unit. Moscow Mayor Sergei Sobyanin confirmed damage to a facility on the refinery grounds and said nobody there was hurt. Russian authorities reported two deaths in the wider Moscow region. More than 400 flights at Moscow airports were delayed because of the attack, Russian media reported, as the country entered the final day of voting in parliamentary elections.

Ukrainian President Volodymyr Zelensky said an oil industry facility and a logistics site in the Moscow region were hit, with weapons including Flamingo, FP-1 and Liutyi used in the operation. “These are billions of dollars that sustain the war machine,” he said. The refinery, which supplies fuel to the Moscow region, had already suffered damage to its primary crude processing units in repeated strikes in June.