A Russian military column was wiped out in a devastating drone attack in the Kursk region, leaving many dead.
The convoy was transporting equipment to help build pontoon bridges across the river Seym, where up to 3,000 Russian troops are believed to be cut off and facing encirclement.
Ukraine has taken out three main bridges over the river in the last week or so, as it presses home its attack on Russian territory.
In a desperate bid to evacuate troops to the other side of the river, Russian engineers have scrambled to build pontoon crossings.
However, these are particularly vulnerable to rocket and drone attacks by Ukraine‘s army.
A video shot by a local resident and posted to the Telegram Channel Belgorod People’s Republic shows the aftermath of a drone strike on the convoy.
Images show burnt out and abandoned vehicles scattered along a road close to the village of Zvannoye.
More images shot by a Ukrainian drone show vehicles ablaze on the road in the immediate aftermath of the attack.
“The [pontoon] bridges are being pounded hard. Five vehicles have burned,” said the author of the first video clip.
“In any case, there are victims. But they are keeping quiet. ‘We have everything under control,’ they say.”
Ukrainian forces have regularly hit Russian military columns in Kursk, as the Kremlin rushes reinforcements to the area.
Kyiv’s military supremo General Oleksandr Syrsky claims Putin’s army has redeployed up to 30,000 troops from other parts of the frontlines to try and repel the incursion.
Analysts at the US think tank The Institute for the Study of War estimate the Kremlin will need at least 60,000 soldiers to retake lost territory.
Most of the troops do not appear to have been taken from the eastern front, where Ukraine faces a desperate fight to hang on to the strategically important city of Pokrovsk.
The eastern city is a vital transport hub – one of two key rail and road junctions in the Donetsk region
Its capture would threaten the entire region’s logistics for Kyiv’s military, according to Frontelligence Insight – a Ukrainian analytical group.