The elite force bearing the brunt on eastern front

The Azov brigade is tasked with repelling relentless Russian attacks as the invaders have made the most of an artillery mismatch

- Dan Sabbagh

150 Number of glide bombs that Russia is capable of launching into a sector in a day

43 The average age of the Ukrainian army, according to the UK's Royal United Services Institute thinktank

Twenty-five kilometres east of the garrison town of Lyman, a desperate fight has been taking place for months on Ukraine's eastern front. The once verdant Serebryansky pine forest has been reduced to burnt-out stumps, reminiscent of images from the Somme, destroyed by Russian attacks aimed at eliminating Ukrainian foxholes.

Fearful that the frontline could crack last summer, Ukraine's commanders deployed the Azov infantry brigade to the sector. Their task was and is to repel what Maslo, a 29-year-old staff sergeant with the unit's 1st battalion, described as "constant assaults". Occasionally the brigade makes counterattacks on foot.

Poor visibility and a mismatch of equipment makes the fight harder. Maslo described a "more or less stable" artillery mismatch of five to one in favour of the Russians, though he believes it is closer to 10 to one in the most intense sectors of the front, such as during the winter battle of Avdiivka, which fell to the invaders in February.

Russian drone attacks are also proliferating, he added. But perhaps the most serious problem the defenders face are Russian glide bombs, air-launched from as far as 70km away by Su-34 and Su-35 jets.