Kyiv has fiercely denied Russian claims that a Ukrainian sabotage group crossed into Russia and opened fire on civilians.
Mykhaylo Podolyak, an adviser to Ukraine's President Volodymyr Zelensky, said the allegations were a “deliberate provocation” after Russian officials claimed that “saboteurs” from Ukraine had fired at a car in the border village of Lyubechane.
The governor of Russia’s Bryansk region, Alexander Bogomaz, claimed that two men had been killed in the incident and a 10-year-old boy injured. There have been no confirmed reports of Ukrainian soldiers inflicting casualties in Russia.
Mr Podolyak said: “The story about Ukrainian sabotage group in Russia is a classic deliberate provocation. Russia wants to scare its people to justify the attack on another country & the growing poverty after the year of war. The partisan movement in Russia is getting stronger & more aggressive. Fear your partisans...”
In a statement, Russia’s Federal Security Service said it acted together with the military to “eliminate armed Ukrainian nationalists who violated the state border”.
They claimed the “attackers” had been pushed back into Ukraine where a “massive artillery strike” was inflicted on them.
It comes just days after Russian President Vladimir Putin ordered the Federal Security Service to tighten control on Russia’s border with Ukraine.
Ukraine’s military intelligence representative, Andrii Cherniak, interpreted the Russian claims as evidence that Moscow is facing an uprising among its own disgruntled people.
“This was done by the Russians; Ukraine has nothing to do with it,” he told The Associated Press.
British military intelligence said on Wednesday that Russia was launching drone attacks on Ukraine from the Bryansk region, which lies to the north of Ukraine and is closer to its capital Kyiv than other launch sites.
In other developments, Ukrainian forces held out in the eastern city of Bakhmut against Russian attackers on Thursday.
Ukraine says the city has limited strategic value but it is exhausting Russia's invasion force in what has become the bloodiest battle of the war.
"Sooner or later, we will probably have to leave Bakhmut. There is no sense in holding it at any cost," Ukrainian lawmaker Serhiy Rakhmanin said.
The aim was to "inflict as many Russian losses as possible,” he added.
