A heroic Ukrainian soldier who had his throat slit and was buried alive by Russian torturers before crawling for nearly five days to reach safety has described the atrocities he and his comrades faced while in captivity.

The 33-year-old National Guard serviceman, identified only as Vladislav, was captured earlier this month near the city of Pokrovsk in the eastern Donetsk region after Russian forces overran his unit's position.

Despite suffering horrific injuries, including a deep slash across his neck, Vladislav managed to claw his way out of a makeshift mass grave where he had been dumped alongside seven dead comrades.

Although he cannot speak because of the wound to his throat, the father-of-one described the ordeal in written notes that have been shared by his wife and brother.

According to Ukrainian public broadcaster Suspilne, Vladislav, who has a four-year-old daughter, revealed that his fellow prisoners were subjected to horrendous torture at the hands of Russian soldiers.