Drones attacked two oil refineries just 40-50 miles (65-80 km) east of Russia's biggest oil export terminals on Wednesday, sparking a fire at one and causing no damage to the other, according to Russian officials.
Drone attacks deep inside Russia have intensified in recent weeks with strikes on Moscow, oil pipelines and even the Kremlin ahead of a Ukrainian counter-offensive.
At around 0100 GMT a drone struck the Afipsky oil refinery in Russia's Krasnodar region, causing a fire which was later extinguished, Governor Veniamin Kondratyev said.
