A drone closes in on a column of tanks as they advance across a snow-covered field, footage released by Russia's National Guard and geolocated by RFE/RL shows.
The attack took place southwest of the village of Berdin, in Russia's Kursk region, where Ukraine launched a new offensive on January 5.
RFE/RL has also verified Russian drone footage of Ukrainian armored vehicles nearby.
Ukrainian forces launched a surprise offensive in Kursk in August, seizing chunks of territory. They have since resisted Russian attempts to fully expel them.
Official Russian sources have claimed to have stopped the new Ukrainian offensive.
On January 6, the Defense Ministry stated it had destroyed Ukrainian tanks around the village of Berdin and foiled an attempt at a breakthrough.
Russian pro-war blogs also reported from the area.
The MIG Rossyy Telegram channel said Ukrainian forces were moving around Berdin but not attacking it. It said Ukrainian forces were using armored personnel carriers to move infantry into the area.
Satellite imagery from January 5 revealed the area to be pockmarked with craters that were not there three days earlier.
Another Russian military blog, exilenova_plus, posted a video of a Russian soldier in the region saying the situation was "complicated."
Clashes were also reported in several other locations in Kursk, including the villages of Tyotkino, Leonidovo, and Pushkarnoye.
This has prompted speculation that the movements around Berdin were a feint attack -- designed to draw Russian forces in from elsewhere on the front.
The commander of a Chechen unit operating with Russian forces in Kursk, Major General Apti Alaudinov, posted a video saying, "We are registering a concentration of enemy [Ukrainian] equipment in another direction."
In any case, the scale of the Ukrainian operation so far may suggest it has tactical rather than strategic objectives.
"The local target is to capture the town of Bolshoye Soldatskoye... to complicate Russian logistics," military analyst Yan Matveyev told Current Time.
Israeli military expert David Gendelman told RFE/RL it was still unclear what the main thrust of the attack would be. But he said the intention may be to secure Ukraine's foothold in Russia.
"If there's been a political directive to hold on to that foothold, an additional attack makes sense," he added. "Combat action is always a way to implement a political decision."
While the location of the fighting can be pinned down, the course of the battle is harder to gauge.
One Ukrainian military blogger reported "panic" along the Russian lines and said North Korean units fighting for Moscow had also been encountered.
Russian pro-war blog Rybar said some Ukrainian military vehicles entered Berdin at one point in the fighting.
Various Russian blogs reported Russian attacks destroying columns of Ukrainian armor elsewhere in Kursk.
The Ukrainian General Staff issued a statement on January 6, saying, "In Kursk region, Ukrainian defenders repelled 17 attacks by [Russians], 45 more battles continue."
RFE/RL could not verify the battlefield claims.
Ukrainian military analyst Pavlo Narozhniy told RFE/RL he would be cautious about evaluating reports from Kursk for now.
The main questions, he said, related to Ukraine's capacity for a new offensive.
"Do we have a sufficient number of free reserves, enough artillery to demolish the enemy's [Russia's] defenses there, which have already entrenched themselves in positions? Do we have a sufficient number of armored vehicles?"
The coming days may present some answers to those questions.
