Ethnic Russian dissidents fighting alongside Ukraine have taken over towns in the Russian region of Belgorod as they try to reclaim their country from President Vladimir Putin.

Exiled Russian politician Ilya Ponomarev, a representative of the fighters, told Newsweek on Monday that the Freedom of Russia Legion and the Russian Volunteer Corps liberated Kozinka and had already entered Grayvoron.

A Ukrainian spokesman for the Defense Ministry's Main Intelligence Directorate later reported that Kyiv's troops were operating to establish a security zone for civilians.

"The events in the Belgorod region and other border areas are the result of a full-scale invasion and aggressive war of Putin's Russia against Ukraine," spokesman Andriy Yusov argued. "Yes, citizens of the Russian Federation ... took responsibility for these events."

"I think that we can only congratulate the decisive actions of the opposition-minded citizens of Russia, who are ready for an armed struggle against the criminal regime of Putin," he added.

The RVC also announced the territorial gains, with the group posting video footage of members near road signs in the Belgorod region through its social media accounts.

It was then partially confirmed by Vyacheslav Gladkov, the Russian regional governor of Belgorod, who announced through Telegram that "a sabotage and reconnaissance group of the Armed Forces of Ukraine" had entered Grayvoron.

"The armed forces of the Russian Federation, together with the border service, the Russian Guard, and [Russia's Federal Security Service] the FSB, are taking the necessary measures to eliminate the enemy. I will report the details," Gladkov said.

It comes as Ukraine prepares for an imminent, full-fledged offensive against Russian-occupied territory in the southern and northeastern parts of the country, the Financial Times noted.

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