The Afipsky oil refinery in Russia's southern Krasnodar region has been hit, and explosions went off at the plant, videos on social media show. Thick smoke is drifting towards Krasnodar.

Clips spreading online show blasts inside the plant, followed by a thick column of smoke.

The refinery makes diesel, petrol components and jet fuel. Since an upgrade, it can process about 9.1m tonnes of crude oil a year, with a refining depth of up to 93%. That makes it one of the biggest refineries in southern Russia.

Journalist Tatyana Popova wrote on Facebook that the plant is of critical military importance to the Russian army and is a main link in fuel supplies to the southern front. Fuel from the refinery goes directly to Russian military vehicles and aircraft in the war against Ukraine.

The Krasnodar region lies close to the southern front. This makes the plant the most important base from which Russian troops get fuel and lubricants.