Drone footage shows a Russian tank column coming under fire on the outskirts of Kyiv.
A Russian tank commander was killed in the attack in the town of Brovary, the Ukrainian military claimed.
The footage, taken from a Ukrainian drone, shows three Russian tanks in the village of Skybyn before they are joined from the north by at least 20 Russian vehicles, including tanks and a TOS-1A, the thermobaric missile launcher system Russia recently confirmed it had used in Ukraine.
Russian forces ambushed
The vehicles turn and stop on the north side of the village before artillery shells and rockets begin to explode around them.
The closely grouped tanks appear to be thrown into disarray by the attack, eventually turning to retreat from the town.
A military expert, Air Marshal Philip Osborn, said the grouping of the vehicles suggests they did not anticipate an attack.
"In regards to grouping, you would only group in that way if you felt relatively secure from attack," he told Sky News. "This video proves that was a misjudgement."
Russian tank commander 'killed'
Intercepted radio communication in audio released alongside the video says they have been "ambushed" as multiple strikes hit the column.
Footage shows somebody down on the floor as others rush to help.
The thermobaric missile launcher can be seen to fire, though it is unclear if that was on purpose.
As they retreat the Russian vehicles bunch up together.
Ukrainian forces claimed a Russian tank commander, Colonel Andrei Zakharov, was killed during the assault.
'Questionable tactics'
The Ukrainian Ministry of Defence said the Russian forces "suffered significant losses in personnel and equipment" and the tank column was forced to retreat and go on the defensive.
Footage taken in the aftermath of the ambush shows burning Russian vehicles on the road.
Rob Lee, a military expert and senior fellow at the Foreign Policy Research Institute, told Sky News: "The Russian forces in the video demonstrated some questionable tactics.
© Other Russian forces are advancing towards Kyiv"They are quite close to Kyiv and moving on a likely avenue of approach, where the Ukrainians would expect them to come from, and yet the column isn't dispersed at all, leaving them vulnerable to artillery fire."
'Difficult night' on outskirts of Kyiv
Russian forces are attempting to advance on Ukraine's capital, Kyiv.
Artillery fire has been heard on the western edge of the city, deputy interior minister Vadym Denysenko said.