The Ukrainian military said a short while ago that Russia is planning to strike the Azovstal steel plant in Mariupol.
Control of this steel factory has become a focal point in the battle for control of Mariupol, with fierce fighting and even reports of hand-to-hand combat in the warrens of the massive industrial complex used by Ukrainian defenders.
The Azovstal iron and steel works is one of the key operating bases left for the several thousand Ukrainian fighters remaining in the besieged city – but the exact numbers using it are unclear because of a lack of reliable information, experts say.
Rumours it had been attacked by chemical weapons have been circulating, but the BBC has not been able to verify these allegations.
Dr Aglaya Snetkov, an expert in Russian foreign and security policy from University College London, explains the factory has been a key objective through the weeks-long siege of the Black Sea port city.
However, she explains the reason the Soviet-era facility has so far resisted capture is that it was built to withstand significant damage, and it is so large that it has proven difficult to flush out fighters – which include elements from the far-right, nationalist Azov battalion – based there.
Snetkov says the plant, as well as Mariupol more broadly, has demonstrated the challenges of urban warfare and capturing areas with a “lot of fighters that keep going and can essentially have hideouts”.
The heavily defended area is one of Mariupol’s last remaining pockets of resistance, intelligence expert Justin Crump explains.
Describing the nature of the fighting, the former British Army officer describes it as complex battles in amongst dense industrial buildings.
Crump says the focus of the Russian assault has primarily been bombing the area as part of a painstaking and slow tactic of “wearing down the defenders” occupying the vast site.
He explains this means they have been using heavy artillery to destroy buildings which could be used by defenders, advancing afterwards to reduce the deaths of their own soldiers.
Crump adds the Ukrainian troops are in surprisingly “good order” given the brutal bombardment for many weeks, but are in an increasingly difficult situation after their supplies of ammunition and food have been cut off for over a week. Many are increasingly being forced to surrender, he says.
story by Adam Durbin
