On the Ukrainian frontline, drone units are operating in tandem with artillery to specifically target Russian troops. Using the drones has proved invaluable, as a means to make the most of dwindling ammunition supplies and conserving what's left as Ukraine battles to hold on to towns and villages across different parts of the country. Bel Trew visited one drone unit, fighting along an almost deserted frontline as politicians struggle to secure the ammunition needed to avoid ceding control of territory.