Seizing Lyman represents a significant moment in the slow advance of Russia's proxy forces in eastern Ukraine. The battle for the city has been intense, even if Ukrainian forces started pulling back from it earlier this week. It's the second major success for Russia this week, following the fall of Svitlodarsk further south.

Lyman is not a big city in itself, but it gives Russia's proxies control of a key east-west road. It also means they are now within 20km (12 miles) of the city of Slovyansk, to the south-west. Slovyansk is a major transport and supply hub for Ukraine, even though the trains stopped running there weeks ago.

The other big battle is further to the east, where Russian forces are targeting the twin cities of Severodonetsk and Lysychansk. Local officials say there is heavy fighting on the outskirts of Severodonetsk and two-thirds of the city is surrounded.