Ukraine hit a Russian oil refinery in Ryazan, south of Moscow, in a new drone attack on Russia’s energy infrastructure, authorities have said. Ukraine has launched drones into Russia regularly since last year as the war between the two drags on, increasingly targeting sites such as factories and oil refineries deep inside Russia. “As a result of an operation by the Defence Intelligence of Ukraine on the night of May 1, a UAV (drone) was used to hit the Ryazan oil refinery in Russia,” Ukraine’s special services said in a statement to AFP.