Russian volunteers fighting for Ukraine drove tanks and armoured vehicles into Russia in a three-pronged raid across the border.

Three separate units of Russian-born soldiers clashed with Moscow security services as they claimed to have captured a village in an attack that is likely to anger the Kremlin.

The raid – a possible distraction effort as Ukraine suffers losses on the front lines – came as Ukrainian drones struck key oil refineries, exacerbating a petrol crisis in Russia.

The Russian Freedom Legion and the Siberian Battalion announced their joint operation into Russia on Tuesday morning.

The Siberian Battalion was said to be working directly for the Ukrainian army, in contrast to previous raids that were directed by secret intelligence agencies.

AIlya Ponomarev, a former Russian politician living in exile in Ukraine, said that the anti-Kremlin separatist groups entered the frontier regions of Belgorod and Kursk.

Ukraine’s HUR military intelligence agency said that a third unit, the Russian Volunteer Corps, was also participating in the operation.

Andrii Yusov, the HUR’s spokesman, said that the groups comprised Russian citizens that were acting as part of “Ukraine’s security and defence forces”.

He told Ukraine 24: “[They are] helping to liberate Ukraine from the Russian invaders.

“But these are citizens of the Russian Federation, and at home (in Russia) they have the right to do whatever they think is necessary in this situation to protect their civil rights and free their country from the Russian Putin dictatorship.”

Russia’s defence ministry said that it had “thwarted Kyiv’s attempt to make a breakthrough into the Russian border territory”, adding the attack was staged “simultaneously in three directions”.

It described the attackers as “Ukrainian terrorists” rather than Russian citizens fighting against Vladimir Putin.

Meanwhile, Ukraine struck one of Russia’s largest oil refineries in a long-range barrage targeting at least seven regions.

The Russian Freedom Legion and Russian Volunteer Corps have previously been involved in similar raids into the Belgorod region.

But it appears to be the first armed foray by the Siberian Battalion, which was formed in December, and unlike the other Russian volunteer battalions fighting for Ukraine is part of Kyiv’s armed forces.

“Like all our fellow citizens, in the Legion we dream of a Russia freed from Putin’s dictatorship,” the Russian Freedom Legion wrote on social media.

“But we don’t just dream: we work hard to realise those dreams. We will take back our land centimetre by centimetre from the regime.

“Russians will sleep well, will not be afraid of the doorbell, and will not be afraid to say what they think. Russians will vote for whom they want, not for whom they have to. Russians will live freely.”

The group later published footage purporting to show the unit operating in Tyotkino, a Kursk region village less than a mile inside Russia’s border. It appeared to show the destruction of a Russian armoured vehicle in the settlement.

Intense battles on Russian soil

Further footage taken through a house window appeared to show a tank driving past flying the Russian Freedom Legion’s white-and-blue flag.

The Siberian Battalion released video footage purporting to show its fighters advancing through a heavily forested area.

“Intense battles are ongoing on Russian soil,” it said.

Amid the gun battles between the Ukraine-backed forces and Russia’s security services, more than two dozen Ukrainian drones were reported over central Russia.

Moscow’s defence ministry said that it had intercepted most of them as they crossed the frontier, with images of air-defence systems and air-raid warnings in Belgorod circulated on social media.

Drones were also reported over the Moscow region and near St Petersburg.

Russian officials said the attacks had sparked a fire at Lukoil’s plant in the Nizhny Novgorod region.

A fire also broke out at an oil reservoir in the Oryol region, Russian officials added.

Meanwhile, a Russian military transport plane caught fire and crashed in the Ivanovo region north-east of Moscow, Russia’s defence ministry said on Tuesday.

Footage showed the Il-76 aircraft losing altitude with one of its engines on fire. Other video clips circulated on social media showed a dark plume of smoke rising into the sky from the crash site.

The Ivanovo region is located more than 700 kilometres from the Ukrainian border.

There was no suggestion that Ukraine was behind the crash. Moscow said that it was caused by a fire in the engines during take-off.