The Slavyansk oil refinery in Russia’s Krasnodar region caught on fire on Sunday after a Ukrainian drone attack and one person died from a suspected heart attack, local officials said. Videos online showed explosions and fire, along with the sound of drones approaching the site. On Sunday morning, the Russian defence ministry reported 35 Ukrainian drone incursions, including four in the Moscow region and two in the neighbouring Kaluga and Yaroslavl regions. More Ukrainian drones attacked in the Belgorod, Kursk and Rostov regions bordering Ukraine, and in the southern Krasnodar region, the defence ministry said. Ukraine’s president, Volodymyr Zelenskiy, praised the Ukrainian military for its new “long-range capability”, in a statement posted on Saturday night. “What our own drones are capable of is a true Ukrainian long-range capability. Ukraine will now always have a strike force in the sky,” he said on social media. Zelenskiy’s comments followed Ukrainian drones striking two Rosneft oil refineries in Russia’s Samara region, leaving one facility on fire on Saturday, the region’s governor said. The Volga river region’s Syzran refinery was on fire, Dmitry Azarov said on Telegram. Officials also confirmed an attack on the Novokubyshev refinery. Numerous other attacks during the past week have caused major damage to Russian oil refineries. Russia accused Ukraine of using “terrorist activities” to try to disrupt its presidential election and former president Dmitry Medvedev decried as “traitors” the scattered protesters who started fires at voting booths and poured dye into ballot boxes. A Ukrainian drone dropped an explosive close to a polling station in the annexed Zaporizhzhia region of Ukraine, Russian state news agency Tass said. No injuries or damage were reported and Reuters could not independently verify the incident. Attacks continued on Russia’s Belgorod oblast, with the Russian ministry of defence claiming air defence shot down 15 rockets. A man and a woman were killed in Belgorod oblast on Saturday, and another person was killed by Ukrainian shelling in the Russian city of Grayvoron, regional governor Vyacheslav Gladkov said on the Telegram messaging app. The fresh bombardments on Saturday prompted authorities to close schools and shopping centres. Five people were wounded when a Ukrainian drone hit a car in the village of Glotovo, two kilometres (1.25 miles) from the Ukrainian border, Gladkov said. Kremlin spokesperson Dmitry Peskov told state media Vladimir Putin was being “constantly briefed” by his military leaders on the situation at the border. Putin is all but certain of victory in the election after dissent has been crushed. Russia’s defence ministry said on Saturday that Ukrainian “reconnaissance groups” had attempted an incursion from Ukraine’s Sumy region. That followed an armed incursion claimed by Ukraine-based Russian opponents of the Kremlin on Tuesday in the Belgorod and Kursk regions. Russia’s defence ministry claimed its security forces killed 30 fighters. In contrast, the Russian Volunteer Corps – one of the groups that claimed to have crossed the border on Tuesday – released a video saying it had captured 25 Russian soldiers. Resistance forces set off an explosion near a polling station in Russian-occupied Skadovsk in the Kherson oblast, injuring five Russian soldiers, the national resistance centre of Ukraine said. The explosion forced Russian administration in Skadovsk to cancel voting at polling stations and allow it only at places of residence, the centre said. There had been 11 attempts to set fire to polling stations in Russia, along with 19 cases of ballot boxes being spoiled with greenery and paint, Nexta reported. Russian authorities have proposed eight-year prison sentences for those involved. The death toll in the Russian attack on civilian infrastructure in Odesa rose to 21 after an injured emergency worker died in hospital. The ballistic missile attack blasted homes in the southern city on Friday, followed by a second missile that targeted first responders, officials said. It was Moscow’s deadliest attack in weeks and caused the British defence secretary, Grant Shapps, to abandon a trip because of a Russian missile threat. More than 50 people were still in hospital, Odesa deputy mayor Svitlana Bedreha said on Saturday, according to Ukrainian state media. Russian shelling killed a 51-year-old man in the Donetsk oblast and injured another, regional governor Vadym Filashkin said. Russians shelled the Donetsk oblast about 11,000 times this week, Filashkin said. There has been a record growth in the number of Russian men ages 31 to 59 with disabilities, the UK defence ministry said in its daily intelligence briefing. “The increase in the number of men with disabilities was most likely due to the growth in military invalids,” the UK defence ministry said. “This is almost certainly the case. A significant majority of the over 355,000 casualties that the Russian armed forces have suffered as a result of the conflict in Ukraine have been wounded personnel.”