Kirishi, Sept. 14 -- Ukrainian drones attacked the Kirishi oil refinery in Russia's northwest, one of the country's largest, sparking a fire when debris fell from a shot-down drone, Russian officials said on Sunday, France 24 reported.

The strike comes amid escalating drone warfare as tensions persist in the deadliest European conflict since World War Two.

Surgutneftegaz's Kirishinefteorgsintez refinery, one of Russia's top two refineries, was targeted by Ukrainian drones, Russian officials confirmed.

Alexander Drozdenko, governor of the Leningrad region, said three drones were destroyed in the Kirishi area and that the fire, caused by falling debris, had been extinguished. "No one was injured," he added, according to France 24.

Ukrai...