There are increasing concerns for the welfare of more than two-hundred and fifty Ukrainian fighters who surrendered to Russian forces at the Azovstal steelworks in Mariupol after weeks of desperate resistance.

The surrender brought an end to the most devastating siege of Russia’s war in Ukraine and allowed President Vladimir Putin to claim a rare victory.

Buses left the steelworks in a convoy escorted by Russian armoured vehicles, with five arriving a Russian-held town, where Moscow said wounded fighters would be treated.

While both Russia and Ukraine spoke of a deal under which all Ukrainian troops would abandon the steelworks, many details are yet to be made public, but the Kremlin said Putin has personally guaranteed the prisoners would be treated according to international standards, and Ukrainian officials said they could be exchanged for Russian captives.