Russian troops have beaten back an attempt by a Ukrainian force to infiltrate its border in a different region to Kyiv's incursion onto Russian territory, Moscow says, while Ukrainian drones have struck near an air base in southern Russia.
The governor of Bryansk region, Alexander Bogomaz, said the attack by a Ukrainian sabotage and reconnaissance team on Wednesday was thwarted by Russian border guards and military units.
It took place about 240km from the site of Ukraine's incursion into the neighbouring Kursk region in western Russia, suggesting the Kyiv government aimed to carry the war to more border areas.
Authorities in Kursk said on Thursday they had begun installing concrete shelters to help protect civilians amid the Ukrainian incursion.
Ukrainian troops piled through the Russian border into Kursk on August 6 in a surprise assault after its troops had failed to make any significant gains on their own territory since late 2022.
Kyiv has announced a string of battlefield successes since mounting the action, but Moscow has steadily pushed forward in eastern Ukraine, pressuring troops worn down by hard years of fighting following Russia's invasion of Ukraine in February 2022.
Russia has repeatedly said the Ukrainian offensive has been halted, but Ukraine has continued to tout advances.
Ukrainian Defence Minister Rustem Umerov told a visiting delegation of US congressmen on Wednesday that Kyiv's attack on Kursk was intended to protect Ukraine.
"Our goals there (in Kursk) are to clear the border from Russian military threats and make enemy shelling and attacks on our towns and villages impossible," Umerov said in a statement.
The incursion has boosted morale among Ukrainians as they prepare to mark 33 years since independence from the Soviet Union on Saturday.
The US embassy in Kyiv however warned on Thursday there was a heightened risk of Russian missile and drone attacks throughout Ukraine in the coming days connected to Independence Day.
Ukraine conducted a drone attack on Russia's Marinovka military airfield in the southern Russian region of Volgograd, striking a storage site for fuel and glide bombs, a security source in Kyiv said on Thursday.
Regional governor Andrei Bocharov posted on Telegram that no one had been hurt, without naming which facility had been attacked.
Russia's defence ministry said it had shot down 28 drones over Russian territory.
Ukraine's President Volodymyr Zelenskiy said on Thursday he and his army chief had visited the border region of Sumy near the border with Russia.
Ukrainian troops had taken control of one more village in the Kursk region, he said.
Ukrainian officials have previously said Kyiv controls more than 90 settlements there.
The Ukrainian military's General Staff said the fighting on the eastern front remained intense and that Russian troops had launched 53 assaults and offensive actions on the front to the east of the transport hub of Pokrovsk in the past 24 hours.
The Ukrainian navy said its forces conducted an attack on a Russian ammunition and fuel storage site on the Moscow-held Kinburn Spit that juts out into the Black Sea in occupied southern Ukraine.
Russia said on Wednesday its forces had advanced in eastern Ukraine and had begun to push back Ukrainian forces in the Kursk region, though a senior commander cautioned that Ukrainian forces were regrouping for another possible attack
Ukraine has closely guarded its main aims in Kursk region but said it has carved out a buffer zone from an area Russia has used to pound targets in Ukraine with cross-border strikes.
