A massive explosion rocked a Russian oil refinery as Vladimir Putin gears up for the country’s election.

The news comes as dissident groups based in Ukraine turned the Russian border into an active combat zone attempting to take over towns and disrupt the vote that is widely seen as rigged.

Video posted to social media shows a huge blast purportedly at a refinery in the Kaluga region of Russia southwest of Moscow.

Posting on Telegram, local outlet RBC Ukraine claimed Kyiv’s intelligence service – the GUR – attacked the refinery overnight.

It said: “GUR operation. In the Kaluga region, drones attacked an oil refinery. A source in the Defense Forces told RBC-Ukraine that drones attacked the Pershii Zavod petrochemical enterprise, which is engaged in oil processing.

“According to the publication, this is an operation of the GUR of the Ministry of Defense.”

The news comes as pro-Ukraine Russian fighters launch attacks on Russian territory.

On Wednesday, The Freedom for Russia Legion – a group of Russian dissidents fighting for Ukraine, claimed it had gained control of the village of Tyotkino in Russia’s Kursk region.

Similar groups called The Siberian Battalion and The Russian Volunteer Corps also announced they were involved in attacks.

The Russian Defence Ministry claimed it had repelled the attacks, killing 60 Ukrainian soldiers as they tried to cross the border.

The Pro-Ukraine groups launched another attack on Thursday.

Sim Tack, chief military analyst at Force Analysis, told France 24: “Currently, there are still battles around Tetkino and pro-Ukrainian forces still seem capable of controlling part of this locality.”

Huseyn Aliyev, a specialist in the Russia–Ukraine war at the University of Glasgow, added that the incursions are “very similar to what happened in the spring and summer of 2023.

“Moscow has built a defensive line – similar to the one it set up in Ukraine – about twenty kilometres inside Russian territory.”

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