The strike damaged refinery equipment, one port berth and five homes – windows were broken in four apartment blocks and a private house – the Krasnodar operational headquarters said on the Telegram messaging app.

Tuapse in the Krasnodar region lies in southwest Russia on the Black Sea and about 350km to the nearest parts of Ukraine’s mainland across the Sea of Azov.

“The refinery blaze was put out after burning about 300sq m,” it said, but the authorities did not provide details on the extent of the damage to the oil refinery’s equipment or whether operations were halted.

Tuapse is one of Russia’s key Black Sea outlets for oil products, anchored by Rosneft’s export-oriented Tuapse refinery, which has the capacity to process about 240,000 barrels of crude oil per day and supplies products such as naphtha, fuel oil and diesel.

The port and the refinery have been hit repeatedly by Ukrainian drone attacks during the war that Russia launched nearly four years ago, with past strikes reported to have sparked fires and at times disrupted operations.

Several Ukrainian media, including the RBC-Ukraine media outlet, posted photos on Telegram appearing to show a large fire burning in the distance at night, with a communications mast silhouetted in the foreground.

There was no immediate official comment from Ukraine about the attack.

Reuters could not independently verify the report or the extent of the damage.

SHOT, a Telegram news channel with sources in Russia’s security services, said a series of explosions was heard late yesterday in Tuapse.