Ukraine's Azovstal Plant: Last Bastion Of Mariupol's Resistance

The vast Azovstal iron and steelworks is the last hold-out of Ukrainian forces in the devastated port city of Mariupol after weeks of Russia's ferocious onslaught.

Russian leader Vladimir Putin on Thursday ordered his military to impose a blockade so tight "that not even a fly can escape" around the plant.

Ukrainian President Volodymyr Zelensky said "about a thousand civilians, women and children" and hundreds of wounded were also sheltering at the industrial complex.

The remaining Ukrainian forces have refused to surrender but have warned supplies were running out and urged international mediation to help them evacuate.

Soviet-era behemoth
Perched on the edge of the Sea of Azov, the plant dates back to the early 1930s when Soviet authorities ordered the construction of an ironworks in the coastal city of Mariupol.

Production began by 1933 but was hastily halted shortly after Germany launched its invasion of the Soviet Union during World War II in 1941.

In 1943, retreating German troops blew up key facilities at the plant, but the factory was relaunched within a few years after Soviet forces took control.  

One of Europe's largest
In 2006, the complex was bought by the Metinvest group controlled by Ukraine's richest man Rinat Akhmetov.

Once reputed to be close to Moscow, Akhmetov has thrown his weight behind the authorities in Kyiv since a Russian-backed insurgency began in 2014.

And he denounced Russian troops for committing "crimes against humanity against Ukrainians" after the Kremlin launched its invasion on February 24.

Prior to Moscow's assault, the Azovstal plant had a capacity to produce 5.7 million tonnes of iron and 6.2 million tonnes of steel a year, Metinvest said, making it one of the largest metalworks in Europe.

The mammoth factory provided employment for thousands of people and dominated the cityscape of Mariupol.

'City within a city'
Stretching over some 11 square kilometres (4.2 square miles), the Azovstal complex is a sprawling warren of rail lines, warehouses, coal furnaces, factories, chimneys and tunnels seen as ideal for guerilla warfare.  

"It's a city within a city," Eduard Basurin, a representative for pro-Russian separatists in the eastern Donetsk region, said earlier this month.  

"There are several underground levels that date back to Soviet times which you can't bombard from above. You have to go underground to clean them out, and that will take time."

Putin said in his orders Thursday that an assault was "impractical".

"There is no need to climb into these catacombs and crawl underground through these industrial facilities," he said.

Russia has resorted to pounding the complex with huge bombs launched from aircraft as it sought to break the resistance of the Ukrainian troops holed up there.  

Drone images broadcast on Sunday by the Russian state agency RIA Novosti showed the widespread destruction wrought by Moscow's besieging forces.

The footage showed a desolate hellscape with a series of buildings that had been completely blown up, some still smouldering.

(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)