Moscow says armed insurgents who crossed the border from Ukraine to launch attacks in Russia’s Belgorod region have been defeated.
Villages in the border region were evacuated after coming under sustained shellfire.
Russia says that 70 of the attackers have been killed and insists the fighters are Ukrainian.
But Kyiv has denied involvement and two Russian paramilitary groups have said they were behind the incursion.
Monday’s raid appears to have been the largest cross-border incursion since Russia’s full-scale invasion of Ukraine 15 months ago.
It led Moscow to declare a counter-terrorism operation in Belgorod, giving the authorities there special powers to clamp down on communications and people’s movements. The measures were lifted this afternoon.
Russia’s defence ministry said a “unit of the Ukrainian nationalist formation” invaded its territory and were responsible for heavy shelling on the Kozinka checkpoint and the Gravoronsky district in the Belgorod region on Monday.
In a statement published on Telegram today, the ministry said 70 “Ukrainian terrorists” had been killed and the rest of the fighters had now been driven back to the Ukrainian border.
But Ukrainian officials said those behind the incident were from groups called the Liberty of Russia Legion and the Russian Volunteer Corps (RVC).
Ukrainian Deputy Defence Minister Hanna Maliar told Ukrainian TV today that they are Russian patriots who want to change the political regime in the country.
The two paramilitary groups told Ukraine’s public broadcaster Suspilne on Tuesday that they were creating “a demilitarised zone on the border with the Russian Federation from which they will not be able to shell Ukraine”