Russian forces have attacked along a broad front in eastern Ukraine as part of a full-scale ground offensive to take control of the country's eastern industrial heartland.
Ukrainian officials say Russian forces are focusing in this ``new phase of the war'' on taking full control of the Donbas.
Moscow-backed separatists have been fighting Ukrainian forces for eight years in the mostly Russian-speaking region.
The stepped-up assaults in eastern Ukraine began along a front of more than 300 miles.
The Russian military also has continued to blockade and shell the strategic port city of Mariupol and fire missiles at other cities.
A commander in Mariupol says Russia dropped bunker-buster bombs on a steel plant where the regiment was holding out.