Civilians are fleeing towns and cities in eastern Ukraine as Russian forces advance. This comes over a threatening soundtrack of air raid sirens and booming artillery.

Negotiating narrow apartment building staircases, volunteers carry the elderly and infirm in their arms, in stretchers or in wheelchairs to waiting minibuses, which then drive them to central staging areas and eventually to evacuation trains in other cities.

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“The Russians are right over there, and they’re closing in on this location,” Mark Poppert, an American volunteer working with British charity RefugEase, said during an evacuation in the town of Bakhmut on Friday.

“Bakhmut is a high-risk area right now,” he said. “We’re trying to get as many people out as we can in case the Ukrainians have to fall back.”

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He and other Ukrainian and foreign volunteers working with the Ukrainian charity Vostok SOS, which was coordinating the evacuation effort, were hoping to get about 100 people out of Bakhmut on Friday.

Earlier, the thud of artillery sounded and black smoke rose from the northern fringes of the town, which is in the Donetsk region in Ukraine’s industrial east. Donetsk and the neighbouring region of Luhansk make up the Donbas, where Moscow-backed separatists have controlled some territory for eight years.

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The evacuation process is painstaking, physically arduous and fraught with emotion.

Many of the evacuees are elderly, ill or have serious mobility problems, meaning volunteers have to bundle them into soft stretchers and slowly negotiate their way through narrow corridors and down flights of stairs in apartment buildings.

Most people have already fled Bakhmut: only around 30,000 remain from a pre-war population of 85,000. And more are leaving each day.

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Fighting has raged north of Bakhmut as Russian forces intensify their efforts to seize the key eastern cities of Sieverodonetsk and Lysychansk, 50 kilometres (30 miles) to the northeast. The two cities are the last areas under Ukrainian control in the Luhansk region.

Northwest of Bakhmut in Donetsk, Russia-backed rebels said Friday they had taken over the town of Lyman, a large railway hub near the cities of Slovyansk and Kramatorsk, both which are still under Ukrainian control. On Thursday, smoke rising from the direction of Lyman could be seen clearly from Slovyansk.