A video shared on social media appears to show a damaged British-made Challenger 2 tank.
A video shared on social media and analysed by BBC Verify shows a badly-damaged British-made tank.
A western defence source confirmed to the BBC the footage shows a Challenger 2 tank and that all crew survived.
It is the first verified sighting of a Challenger 2 on the frontline since Russia invaded Ukraine in 2022.
It also the first time the tank has been hit by enemy fire, according to former British tank commander Hamish de Bretton Gordon.
The footage – which shows smoke pouring from the vehicle – follows claims from Ukrainian officials that its forces have breached the first Russian defensive lines in southern Ukraine.
BBC Verify has not confirmed precisely where or when the incident took place.
However, the video is consistent with other footage that shows Ukrainian forces deployed in the area around the recently-retaken village of Robotyne in the south-east of the country.
Britain announced earlier this year that it would send 14 Challenger 2 tanks to Ukraine. Tanks were supplied after Ukrainian tank crews were trained in March.