Ukraine says its troops are engaged in heavy fighting with Russian forces to liberate the city of Kreminna, in eastern Ukraine, a place of strategic importance for Kyiv. The Ukrainian army has advanced 2.5 kilometres over the past week in the direction of Kreminna, according to regional authorities, while Russia is consolidating its defence there. "If we will liberate Kreminna we will stop the supply for Russian army" for three other important locations and "break their defence in Lugansk region", says tank commander Vlad, speaking to AFP from Yampil, a liberated town now at ten to 15 kilometres from the frontline. IMAGES AND SOUNDBITES