The Kremlin has blamed the incursion in Belgorod as a move aimed to distract attention from the eastern Ukrainian town of Bakhmut.

Russian forces claim to have captured Bakhmut in its entirety after more than nine months of attritional fighting, while reports suggest there is some residual fighting seen in the outskirts of the city, but that the Ukrainian forces have lost control of the last streets of multi-story buildings inside city limits.

Kremlin spokesperson Dmitry Peskov said president Vladimir Putin had been informed about the territorial conflict in Belgorod, and that work was under way to drive out the “saboteurs”, the state-run RIA Novosti news agency reported.

“We understand perfectly well the goal of such a diversion — to divert attention from the Bakhmut direction and minimise the political effect of Bakhmut’s loss for the Ukrainian side,” Peskov was quoted as saying.

Ukrainian military intelligence spokesperson Andriy Yusov said the Belgorod operation would create a “security zone” to protect Ukrainians from attacks by Russia, reported the country’s outlet Hromadske.

An unspecified number of drones have been shot down over the Russian frontline Belgorod area by anti-aircraft weaponry, regional governor said today.

The region, which borders Ukraine, has been witnessing fighting since Monday, after what Russian officials called a Ukrainian “sabotage group” crossed the border.

The Kremlin will almost certainly use the incidents of security threats in border regions to support the official narrative that it is the victim in the war, the British Ministry of Defence (MoD) said today.

The ministry pointed to a chain of events between 19 and 22 May wherein “Russian security forces highly likely clashed with partisans in at least three locations within Russia’s Belgorod oblast”, near the Ukrainian border.

The identity of the partisans remains unconfirmed, but Russian anti-regime groups claimed responsibility, the minstry said.

It added that the most serious incident took place near the town of Grayvoran. “As well as small-arms fire fights, there was an uptick in drone or indirect fire attacks near the incidents. Russia has evacuated several villages and has deployed extra security forces to the area,” the MoD said.

“Russia is facing an increasingly serious multi-domain security threat in its border regions, with losses of combat aircraft, improvised explosive device attacks on rail lines, and now direct partisan action,” it said.

The “counter-terrorism operation” in the Russian frontline city Belgorod was ongoing, regional governor said this morning.

He added that the defence ministry and law enforcement agencies are continuing “to clean up” the territory on the border with Ukraine.

“On the situation in the Graivoron district: the cleaning of the territory by the Ministry of Defence together with law enforcement agencies continues,” the governor, Vyacheslav Gladkov, said on the Telegram messaging app.

“I now appeal to the residents of the Graivoron district, who… temporarily left their homes, it is not possible to return yet.”

The governor confirmed one woman died during the evacuation yesterday and reportedly two people were wounded but Russian security forces have not been able to reach them.

The governor of Russia’s Belgorod region has accused a Ukrainian “sabotage group” of entering the town of Graivoron, about three miles (five kilometres) from the Russia-Ukraine border.

Officials said anti-Kremlin militia are said to have launched a cross-border raid from Ukrainian territory – overrunning one Russian village and pushing on into others.

The town also came under Ukrainian artillery fire, he said.

The governor, Vyacheslav Gladkov, claimed eight people were wounded and most residents has left the area but the situation remained “tense”.

A spokesperson for the GUR told Ukraine’s public broadcaster, Suspilne, that the two groups were conducting an operation in the Belgorod region to create a “security strip” to protect Ukrainian civilians. The incursion was being carried out exclusively by Russian citizens, the spokesperson added.

A group calling itself the Liberty of Russia Legion – a Ukraine-based militia led by Russian opposition figure Ilya Ponomarev – says it is now working inside Russia to overthrow Putin.

The group took to Twitter and said it had “completely liberated” the border town of Kozinka. It said forward units had reached the district centre of Graivoron, further east.

“Moving on. Russia will be free!” it wrote.

The group also released a video showing five heavily armed fighters.

“We are Russians, like you. We are people like you. We want our children to grow up in peace,” one said, facing the camera. “It is time to put an end to the dictatorship of the Kremlin.”

In Kyiv, Ukrainian presidential adviser Mykhailo Podolyak tweeted: “Ukraine is watching the events in the Belgorod region of Russia with interest and studying the situation, but has nothing to do with it.

Russia’s Wagner Group is trying to obscure its efforts to acquire military equipment for use in Ukraine, the US State Department said.

Washington has been informed the mercenary force is seeking to move those acquisitions through Mali to aid Russia in its war and is willing to use false paperwork for such transactions, State Department spokesperson Matthew Miller said at a news briefing yesterday.

“There are indications that Wagner has been attempting to purchase military systems from foreign suppliers and route these weapons through Mali as a third party,” Mr Miller said.

“We have not seen as of yet any indications that these acquisitions have been finalised or executed, but we are monitoring the situation closely.”

Mr Miller said Washington has imposed sanctions on a number of people and entities that support Wagner’s military operations, and said the United States would have more to share soon.

A video posted late last night from Belgorod showed a fighter inspecting a captured armoured vehicle and another video showed what it said were fighters operating an armoured vehicle on a country road.

The video was posted by one of the two armed Russian opposition groups, the Russian Volunteer Corps (RVC), carrying out the operations inside Moscow’s territory. Another group, the Liberty of Russia Legion, is also involved in attacking Russian forces in Belgorod, according to the Ukrainian outlet Hromadske which cited Ukrainian military intelligence.

Other videos posted on Russian and Ukrainian social media channels showed pictures and video of what were described as captured Russian servicemen and their identity documents.

The Telegram channel Baza, which has links to Russia’s security services, had earlier published aerial footage apparently showing a Ukrainian armoured vehicle advancing on the Graivoron border checkpoint.

There were indications of fighting in three settlements along the main road leading into Russia, according to Baza.

The Liberty of Russia Legion released a video showing five armed fighters.

“We are Russians, like you. We are people like you. We want our children to grow up in peace,” one said, facing the camera. “It is time to put an end to the dictatorship of the Kremlin.”

The leader of a Russian mercenary group has said he will pull its fighters from Bakhmut after claiming to have captured the Ukrainian city.

Wagner chief Yevgeny Prigozhin said Bakhmut, in the eastern Donetsk-Oblast region, had been captured by his private army on Saturday afternoon – a claim Ukraine continues to dispute.

Volodymyr Zelensky’s deputy defence minister Hanna Maliar instead claimed Ukrainian forces have partly encircled the besieged eastern city along the flanks and still control a part of the city.