Fighting desperately to cling on to coal mines that were once the lifeblood of its industrial east, Ukraine's soldiers concede they are struggling against intensifying Russian attacks. "There's only so much we can do. No matter what super warriors are fighting in our ranks, they [ed, the Russians] outnumber us…It hurts," said the chief sergeant of Ukraine's 59th brigade, deployed in the Donetsk region, who goes by the call sign "San Sanych". Russia's army is around six kilometres (four miles) from the centre of Pokrovsk, a formerly thriving mining hub on top of Ukraine's largest coal reserves. The capture of the city and surrounding mines, some of which are even closer to Russian positions, would be a painful blow to Ukraine's army, local communities and the national economy. IMAGES AND SOUNDBITES ARRANGED IN SEQUENCES