In the devastated eastern Ukrainian town of Toretsk, time is running out for anyone wanting to leave.

Russian forces are advancing slowly but surely, pummelling the town night and day with rockets, artillery fire and air attacks, part of a broad advance in the Donetsk region that Ukraine has been unable to stop.

In a residential courtyard a group of mainly elderly residents gather to listen to Ivan, a police officer in camouflage fatigues who is trying to convince them to leave Toretsk with his evacuation team.

Hundreds of officers like him and Ukrainian volunteers are trying to do the same in towns and villages along the frontline before they are reduced to rubble and subsumed into territory held by the Russians.

“Are you all staying?” he asked, speaking firmly and quickly. “Can you not see how the situation is changing? If you think you will sit it out - this is not going to happen.”