MOSCOW/MELBOURNE Russia's Tuapse oil refinery, its biggest on the Black Sea, was damaged in a major Ukrainian drone attack overnight, which sparked a fire, Russian officials said on Monday, though the extent of the damage was not immediately clear.

Debris from the drone, which was shot down, caused a fire at the refinery, which is owned by oil major Rosneft, the officials said. The fire has since been contained, the regional administration said on the Telegram messaging app.

Russia's SHOT and Mash Telegram news channels reported that a series of blasts were heard near the refinery early on Monday.

There were no casualties, officials said. Reuters was unable to immediately verify whether the refinery was operational, or to establish the extent of the damage it had sustained.

Ukraine has been systematically targeting Russian energy infrastructure, in an attempt to disrupt Russia's economy and its ability to fund what the Kremlin calls its special military operation in Ukraine.

Ukrainian officials say the attacks have been carried out in retaliation for Russian strikes on Ukraine's energy system. Russia says the drone attacks by Ukraine amount to acts of terrorism.

Overall, Russia's defence ministry said its air defence systems had destroyed a total of 75 drones launched overnight by Ukraine, including eight near Tuapse.

The Tuapse plant, which has processing capacity of 240,000 barrels per day (bpd) of oil, has been a target of several Ukrainian air attacks since the start of the war that Russia launched against Ukraine in 2022, including on May 17.

The Tuapse refinery produces naphtha, fuel oil, vacuum gasoil and high-sulphur diesel, supplying fuel mainly to Türkiye, China, Malaysia and Singapore.

In 2023, the plant processed 9.322 million metric tonnes of crude oil, producing 3.306 million tonnes of gasoil and 3.123 million tonnes of fuel oil.

Of the 75 drones launched overnight, Russia's ministry said 47 drones had been downed over the Rostov region in southwestern Russia, 17 over the waters of the Black and Azov seas; eight over the Krasnodar region, where Tuapse is located; and single drones over the Belgorod, Voronezh and Smolensk regions.

Russian officials rarely disclose the full extent of damage inflicted by Ukrainian attacks.

Vasily Golubev, governor of the Rostov region, said on Telegram that no one was injured as a result of the attack there, and that no serious damage had been detected.

Reuters could not independently verify the Russian reports. There was no immediate comment from Ukraine.

  - Reuters