A fire has broken out at an oil refinery in southern Russia following a drone attack, a Kremlin-appointed official said on Sunday. The night-time raid in the Volgograd region was repelled by the Russian air defences, Governor Andrey Botsharov wrote on Telegram. However, the falling drone detonated and caused a fire on the refinery site, which had since been extinguished. There were no casualties, the governor said. Moscow has been waging a full-scale war against Ukraine for more than two years. To disrupt Russia’s infrastructure and reduce its war revenues, the Ukrainians have in turn repeated…