Ukrainian troops have advanced 30 km into Russia, making it the deepest and most significant incursion since Moscow launched a full-scale invasion of Ukraine in February 2022.
As the offensive in the Kursk region entered its sixth day, Russia’s Defense Ministry said its forces engaged Ukrainian troops near the villages of Dolbino and Obshi Kolodes.
Foreign Ministry spokeswoman Maria Zakharova accused Kiev of “threatening the peaceful people of Russia.”
President Volodymyr Zelensky, who directly acknowledged the attack for the first time in a speech last night, said 2,000 cross-border attacks had been launched by Russia from Kursk this summer.
“Artillery, mortars, drones. We also register missile attacks, and every such attack deserves a justified response,” Mr Zelensky told the nation in his nightly address from Kyiv.
A senior Ukrainian official told the AFP news agency that thousands of troops were involved in the operation, rather than the small incursion initially reported by Russian border guards.
While pro-Ukrainian sabotage groups have launched relentless cross-border incursions, the Kursk offensive marks the largest coordinated attack on Russian territory by Kiev’s legacy forces.
“We are on the attack. It is to expand the enemy’s positions, inflict maximum losses and destabilize the situation in Russia as they are unable to defend their own border,” the official said.
Russia’s Defense Ministry said on Sunday that “enemy mobile groups have foiled attempts to penetrate deep into Russian territory with armored vehicles.”
But in an apparent admission that Kyiv’s forces have now advanced deep into the Kursk border region, the Defense Ministry said it engaged Ukrainian troops near the villages of Tolpino and Obshchy Kolodez, 25km and 30km from the Russia-Ukraine border.
Footage circulating online and verified by the BBC also appeared to show a Russian strike near the village of Levshinka, 25km from the border.
Ukrainian troops said they captured several settlements in the Kursk region. In the village of Guevo, about 3km into Russia, soldiers filmed themselves removing the Russian flag from an administrative building.
Clips have emerged of Ukrainian troops seizing administrative buildings in Sverdlikovo and Boros, while heavy fighting has been reported in Sudja, home to around 5,000 people.
Ukrainian troops have already pictured themselves outside Chudja at a large gas station involved in transporting natural gas from Russia through Ukraine to the EU, which has continued since the war.
In the Sumy region, bordering the Kursk region, BBC reporters saw armored personnel carriers and tanks moving towards Russia.
Armored parapets have white triangular emblems, which seem to distinguish them from the hardware used in Ukraine itself. Meanwhile, aerial photographs have emerged showing Ukrainian tanks engaged in combat inside Russia.
Photographs examined by BBC Verify also appeared to show Russia building new defense lines near the Kursk nuclear power plant. Ukrainian forces engaged in Obshchy Kolodez were 50km (31 mi) from the facility.
Contrasted satellite images of the same location taken a few days earlier show several newly constructed trench lines nearby, 8km (5 miles) from the plant.
Russia says 76,000 people have been evacuated from border areas in the Kursk region, where a state of emergency has been declared by local authorities.
15 people were injured late Saturday when debris from a Ukrainian missile crashed into a multi-story building in the Kursk regional capital, Kursk, acting regional governor Alexey Smirnov said.
Oleksiy Goncharenko – a Ukrainian member of parliament – praised the move and said it “brings us closer to peace than a hundred peace summits”.
“When Russia has to fight back on their own territory, when the Russian people are running, when people are worried, this is the only way for them to stop this war,” he told the BBC.
The Kursk offensive comes after weeks of Russian advances in the east, where successive villages have been captured by Kremlin forces.
Some analysts have suggested that the Kursk offensive was part of an effort to get Russia to redeploy forces from eastern Ukraine and reduce pressure on Ukrainian defenses.
But a Ukrainian official told AFP there had been little delay in Russian operations in the east until today.
Earlier this week, Russian President Vladimir Putin called the attack a “major provocation.”
Meanwhile, emergency services in the Kyiv region said a man and his four-year-old son were killed in an overnight missile attack near the capital.
Air defenses destroyed 53 of 57 attack drones during the Russian airstrike, Air Force officials said. All four North Korean-made missiles were fired in a barrage, they said.
Russia has been forced to turn to the isolated Asian nation to restock its weapons, with the US accusing Pyongyang of sending large amounts of military hardware.
Elsewhere, Russian officials in the occupied Zaporizhia province said Sunday that a fire broke out at the region’s nuclear power plant.
Yevgeny Politskyi, governor of the Kremlin-based Zaporozhye, said the fire broke out after shelling by Ukrainian forces. He said there was no radiation around the plant.
The main fire at the plant was extinguished early Monday, Russia’s state-run TASS news agency reported.
In a statement released to X, the UN’s nuclear watchdog – the International Atomic Energy Agency – said its on-site inspectors saw “heavy dark smoke” coming from the north of the facility, but insisted there was “no impact”. Nuclear Security.
President Zelensky said in a post on social media that Russian forces had set fire to the plant’s territory.
The site has been under the control of Russian troops and authorities since 2022. It has not produced electricity for over two years and all six reactors have been shut down since April.
With additional reporting by Benedict Carman.