Yevgeny Prigozhin, founder of Russia’s Wagner mercenary force, said in a video published on Friday that the Ukrainian city of Bakhmut was “practically surrounded” by his forces and that Kyiv’s forces had only one road left out.

Prigozhin’s men have spearheaded the assault in eastern Ukraine for months. Moscow regards Bakhmut, which it calls by its Soviet-era name of Artyomovsk, as a useful stepping stone to seize bigger cities like Kramatorsk and Sloviansk.

Prigozhin, wearing a military uniform in the video, called on Ukrainian President Volodymr Zelenskiy to withdraw his forces from the small city.

“Units of the private military company Wagner have practically surrounded Bakhmut. Only one road is left (open to Ukrainian forces) The pincers are getting tighter,” said Prigozhin.

Prigozhin said his forces were increasingly fighting against old men and children rather than the professional Ukrainian army.

The video then showed what looked like three captured Ukrainians – an older man and two young boys – who looked frightened and asked to be allowed to go home. They looked to be speaking under extreme stress.

Prigozhin on Thursday released another video showing his fighters inside Bakhmut. Reuters geolocated the footage to the east of Bakhmut, around 1.2 miles (2 km) from the city centre.