A brief armed incursion into a Russian border village by partisans claiming to fight for Ukraine drew an emergency response from the Kremlin on Thursday, prompting President Vladimir V. Putin to cancel a trip and convene his security council over a rare known case of a raid inside Russia.
What actually happened was immediately shrouded by conflicting claims from pro-Kremlin voices and their opponents, though by the end of the day, the Russian authorities had asserted that the incursion was over and that the group had been driven back into Ukraine.
Mr. Putin, who called off a trip to the Caucasus region to be briefed, denounced the episode as a “terrorist” attack, a label Russia frequently applies to military setbacks in the war in Ukraine, and to the periodic explosions on Russian territory believed to be Ukrainian strikes.
In a televised address, Mr. Putin said, without offering any evidence, that the group had opened fire on civilians. The governor of Bryansk, Aleksandr V. Bogomaz, said on the Telegram messaging app that the group had fired on a vehicle, killing two civilians and injuring a child.
The Russian Volunteer Corps, a group opposed to Mr. Putin and led by a nationalist in exile, claimed on Thursday that it had briefly taken control of the small village, Lyubichane, in the Russian region of Bryansk, near the border with northeastern Ukraine.
The group posted a video online of two armed men outside what appeared to be a medical building in Lyubichane. That footage could not immediately be verified, but the group also posted another video that a New York Times analysis confirmed had been taken in Shushany, a village about 10 miles to the south in the same region.
It is unclear whether the group operates with the assent of the Ukrainian government, as it claims, though it has been fighting against Russian forces. The group said on Telegram that it “came to Bryansk region to show the compatriots that there is hope, that free Russian people with weapons in their hands can fight the regime.”
Russian state news agencies issued conflicting reports about the episode throughout the day. They initially claimed that saboteurs had taken up to six people hostage, but later walked that back, reporting that local officials had no information about hostage-taking.
The Kremlin’s spokesman, Dmitri S. Peskov, told reporters that “all measures are currently being taken to liquidate those terrorists.” Russia’s Tass state news agency said the group had already left Russia by Thursday afternoon.
Ukraine has made no secret of its attacks on Russian positions in areas of Ukraine occupied by Russian forces. But when it comes to cross-border attacks, it has maintained a policy of strategic ambiguity, with officials being deliberately vague or making cryptic statements about explosions or incidents within Russia’s borders.
Ukraine is believed to have struck inside Russia on several occasions, including in December, when a drone launched from Russian soil hit a military base in the city of Ryazan. Russia’s Defense Ministry on Wednesday said that its forces had foiled an attack by 10 drones on targets in Crimea but on Thursday it did not mention blasts in Crimea in its daily bulletin.
On Thursday, Ukrainian officials tried to frame the episode in Bryansk as a symptom of internal Russian schisms.
“This is a sign that Russia can no longer function normally, and this leads to internal destruction,” Andriy Cherniak, a representative for Ukraine’s military intelligence, said in a phone interview.
Oleksiy Danilov, the head of the Ukrainian National Security and Defense Council, said in a statement that Moscow was facing “a movement of Russian antifascist militias.”
But there is widespread support among the Russian public for the Kremlin, and there is no evidence that the Russian Volunteer Corps or other armed groups fighting against the Kremlin have a broad appeal inside Russia.
“This incursion seems to have benefited one group of people alone, and that’s the Russian Volunteer Corps,” said Michael Colborne, a researcher for the news organization Bellingcat who is focused on the far right, and who believes the group’s members are in the low hundreds at most. “Telegram is their primary means of communication, and they’ve more than doubled their subscribers from 16,000 to 33,000 in one day now.”
Mr. Putin has used the war to further assert his dominance over Russian life, driving away citizens opposed to the invasion and cultivating a romanticized view of the military despite its steep losses and stumbling performance on the battlefield over the past year.
Russia’s latest offensive in eastern Ukraine — like its overall war effort over months — has struggled to gain ground, losing significant numbers of tanks, armored personnel carriers and troops in Ukrainian ambushes, minefields and artillery strikes. But bolstered by the mobilization of hundreds of thousands of men, Russia’s military has persisted with its attacks and has inched forward in the city of Bakhmut, which has been virtually annihilated by months of fighting.
The Russian military has also continued to fire long-range missiles and drones at Ukraine’s cities and energy grid. A Russian missile slammed into an apartment building in the city of Zaporizhzhia early Thursday, killing four people, Ukrainian officials said.
President Volodymyr Zelensky of Ukraine condemned Russia for the attack, saying on Telegram that “the terrorist state wants to turn every day for our people into a day of terror.”
Some Russian supporters of the war — including Konstantin Malofeev, an ultranationalist tycoon — cited the Bryansk incursion to demand an escalation of the war.
“The last red lines have been erased today in the Bryansk region,” he wrote on Telegram. “Now anyone who even whispers about peace will be an accomplice of terrorists.”
The fighting is expected to intensify in the coming months. Senior Ukrainian officials have recently hinted that Kyiv could begin a counteroffensive soon, possibly in the Zaporizhzhia region, and indicated that Russia has reinforced its troop presence there.
Daniel Victor contributed reporting.
