Ukraine forces cross into Russia as Putin's men lose ground to Kyiv

It comes as Nato's Secretary General Jens Stoltenberg says that Ukraine is "gradually gaining ground" in its counter offensive against Russian aggression.

A statement posted on Ukrainian MP Yuriy Mysiagin's Telegram account says: "At the moment, the Legion 'Freedom of Russia' is conducting assault operations on the territory of the Belgorod region of the Russian Federation.

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"There are no injured or dead soldiers, the work is going according to plan."

The group is thought to be made up of Russian men who are supportive of Ukraine's cause.

A separate post on a Telegram channel thought to be run by the paramilitary group added: "We continue to cleanse our house of Putin's filth.

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"There is a battle going on, all the details will follow. For Russia! For freedom!"

This isn't the first time the the group has launched attacks on Russian soil, with the Legion launching raids in May aimed at creating a demilitarised zone.

Earlier today Nato's Secretary General Jens Stoltenberg made a surprise visit to Ukraine to discuss the latest developments in the war.

He said that positive battleground advances were being made by Volodymyr Zelensky's troops despite the best efforts of Russia to hold onto ground that it took at the start of its illegal invasion last year.

Speaking during the unannounced visit to Kyiv, the leader of the defence alliance said that he was "constantly pushing" Nato allies to provide more support to Ukraine and speed up delivery.

He reiterated that "every metre that Ukrainian forces regain is a metre that Russia loses".

Taking aim at Moscow's "imperial delusions", he said Ukraine's right was for "their families, their future, their freedom".

He added: "In the conditions of such intense attacks against Ukrainians, against our cities, ports - which are important for global food security - we need a corresponding increase in pressure on Russia and a corresponding increase in our air shield."