Ukrainian soldiers of the Spartan brigade conducted drills on Friday, honing their skills for the battlefield in the Pokrovsk area of the eastern Donetsk region — now the epicentre of fighting.

Once home to about 60,000 people, the city has been under sustained Russian assault for months.

They have formed a pocket around Pokrovsk, though Ukrainian troops still hold the city, and street fighting has yet to begin.

Reports of Russian saboteurs entering the city started to appear, but the military says those groups have been neutralised.

Everything at the training range, only 45 kilometres (28 miles) from the front, is designed to mirror real combat conditions — even the terrain.

A thin strip of forest breaks up the vast fields of blooming sunflowers stretching into the distance until the next tree line appears.

One of the soldiers training, there is a 35-year-old man who goes by his nom de guerre Komrad. He has only recently joined the military. He says he has no illusions that the war will end soon.

“My motivation is that there is simply no way back,” he said.

“If you are in the military, you have to fight. If we’re here, we need to cover our brothers in arms.”

Ukrainian forces are locked in intense battles along the 1,000-kilometer (620-mile) front line that snakes from northeast to southeast Ukraine.

The Pokrovsk area is taking the brunt of the punishment as Russia seeks to break out into the neighboring Dnipropetrovsk region.

Ukraine has significant manpower shortages.

AP video by Vasilisa Stepanenko