Russia Gains Ground in Eastern Ukraine, Tightens Noose Around Key City of Avdiivka

• Russian forces have made gains in eastern Ukraine, including in Avdiivka industrial hub where fighting has been fierce.

• Avdiivka has been a symbol of Ukrainian resistance since 2014 when it briefly fell to separatists.

• Russia now controls areas around Avdiivka and is tightening noose to push Ukraine forces back.

• Ukraine says situation in Avdiivka is "very tense" with Russia attempting to encircle the city.

-Analysts note Russia appears to be suffering major losses of military equipment in assault on Avdiivka.