Fifteen months after Moscow’s troops invaded Ukraine, one of the largest and most daring cross-border attacks since the war began has been carried out in Russia.
On Monday, two anti-Kremlin groups – the Russian Volunteer Corps (RVC) and Freedom of Russia Legion – claimed responsibility for the incursion in the Belgorod region.
Fighting continued for a second day early on Tuesday. A dozen people are reportedly wounded and some residents have been evacuated.
Later on Tuesday, Russia’s Defence Ministry said that the units it blamed had been forced back into Ukrainian territory. More than 70 attackers have been killed, the ministry said, a figure that was not possible to verify.
After accusing Ukraine, Russia opened a “terrorism” investigation. Officials in Kyiv say they had nothing to do with the attacks.
Here is what we know so far:
Where is Belgorod?
Russia’s Belgorod province borders Ukraine’s Luhansk, Sumy and Kharkiv regions.
It is about 600km (373 miles) from the Russian capital, Moscow, and has been a front-line region, serving as a vital base for the Kremlin’s armed forces to launch attacks towards Ukraine.
But Belgorod has also exposed Russian vulnerabilities.
Moscow accidentally bombed Belgorod city last month, while fuel and ammunition stores in the region have been rocked by explosions since the start of the war.
What happened in Belgorod?
Early on Monday, Belgorod Governor Vyacheslav Gladkov raised an alarm with the Kremlin, saying a Ukrainian “sabotage group” had entered Russian territory in the Grayvoron district.
According to Russia, the raiders opened fire with mortars and artillery on residential and administrative buildings and civilian infrastructure. Russian air-defence forces reportedly shot down drones over the region.
Moscow later said it was carrying out a counterterrorism operation.
Gladkov said one elderly lady had died while being evacuated, but that no civilians were killed in the clashes.
He described the situation as “extremely tense”.
Social media users said air raid sirens rang out and that checkpoints had been targeted.
Fighting continued for a second day. At midday on Tuesday, Russia said it had pushed back the attackers and that 70 had been killed.
On Tuesday, the Institute for the Study of War (ISW), a Washington, DC-based based think-tank, said that two “all-Russian pro-Ukrainian” groups had crossed the border with tanks, armoured personnel carriers and other weaponised vehicles, citing Russian sources.
Who was behind the attacks?
Russia accused Ukraine of launching the attacks, but Kyiv has denied involvement.
Throughout the war, Ukraine has not taken responsibility for any attacks against Russia, saying its fight is purely defensive.
Kremlin spokesperson Dmitry Peskov, as quoted by Russia’s state news agency RIA Novosti, said the purpose of the alleged Ukrainian mission in Belgorod was “to divert attention from the direction of Bakhmut”.
Ukrainian President Volodymyr Zelenskyy’s adviser, Mykhailo Podolyak, said on Twitter that Kyiv had “nothing to do with it” and suggested that an “armed guerrilla movement” had emerged to oppose “a totalitarian country”.
Former Russian President Dmitry Medvedev accused the United States, European Union and United Kingdom, which he referred to as “the sponsors of the Kyiv regime”, of being responsible for “sabotage”. Kyiv’s denial was “an absolute lie”, he said.
Ukrainian news broadcaster Hromadske, citing Ukrainian military intelligence sources, said that two armed Russian opposition groups, the Freedom of Russia Legion and the Russian Volunteer Corps (RVC), consisting of Russian citizens, were responsible for the attack on the Belgorod region.
Asked about reports that the attackers were ethnic Russians, Peskov said: “They are Ukrainian fighters from Ukraine. There are many ethnic Russians living in Ukraine. But they are still Ukrainian militants.”
What do we know about the anti-Kremlin militias?
The RVC was founded by a far-right Russian national last August and is comprised of Russians who have been fighting in and for Ukraine against their own country.
The group has also been active over the border in Russian territory, and claimed responsibility for a raid there in March.
The Ukrainian military intelligence agency says the RVC is an independent underground group inside Russia that also has a unit in the Ukrainian Foreign Legion. The Foreign Legion says it has nothing to do with the RVC.
Late Monday, the RVC published video footage on its Telegram feed appearing to show fighters operating an armoured vehicle on a country road inside Russia. The Reuters news agency was able to identify one of the men as Ilya Bogdanov, a Russian national who received Ukrainian citizenship in 2015 after fighting for Kyiv against Russian-backed forces in Ukraine’s east.
The Legion and the RVC completely liberated n/a Kozinka, Belgorod Oblast. Forward units have entered Graivoron.
Russia will be free!
— “Liberty of Russia” Legion (@legion_svoboda) May 22, 2023
The Freedom of Russia Legion – also known as the Liberty of Russia Legion – says it was formed in spring 2022 “out of the wish of Russians to fight in the ranks of the Armed Forces of Ukraine against Putin’s armed gang”.
It says it cooperates with the Ukrainian armed forces and operates under Ukrainian command. It has claimed responsibility for the attack in Belgorod and says it has been fighting in eastern Ukraine.
The Ukrainian military intelligence agency’s spokesperson said on Monday that the attacks in Belgorod only involved Russian citizens and that they were creating a “security zone” to protect Ukrainian civilians. He did not confirm or deny that the forces operating there are a Ukrainian unit.
The Freedom of Russia Legion said on Twitter that it had “completely liberated” the border town of Kozinka in the Belgorod region and its forward units had reached the district centre of Grayvoron, further east.
“Moving on. Russia will be free!” the group wrote.
The attack on Russia has upped the ante and comes just as Moscow announced the capture of Bakhmut, the eastern Ukrainian city levelled by months of fighting.
Kremlin spokesman Peskov cast the attack as an “invasion” of “serious concern”, promising “great efforts in response”.
On Monday, according to Russia’s RIA Novosti, Peskov also said that work was under way to “squeeze out Ukrainian saboteurs from Russian territory”.
According to the UK, the attacks highlight Moscow’s struggles in the war.
“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,” the British defence ministry said.
Meanwhile, Ukraine’s Podolyak has said that Kyiv is continuing to monitor reports “with interest” and is “studying the situation.”