An aerial video showing the Russian attack on the steel plant was posted to social media channels Sunday

https://www.dailymail.co.uk/news/article-10817825/Mariupol-Russian-incendiary-phosphorus-bombs-rain-Azovstal-steelworks.html

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Putin continues brutal assault on Azovstal steelworks: Footage show Russian 'incendiary phosphorous bombs' raining down on last Ukrainian stronghold in Mariupol
An aerial video showing the Russian attack on the steel plant was posted to social media channels Sunday
It showed Russian incendiary munitions raining fire down onto the already heavily damaged buildings below
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'Sparks' - which are actually a grouping of incendiary munitions - fall to the ground and ignite. From a distance, the explosions look almost like fire crackers, but in reality are a series of countless detonations.
The attack is unrelenting, with hundreds of the sparks landing on the roofs and grounds of the steel works and setting them alight.
Ukrainians claimed the video showed Vladimir Putin's forces dropping 9M22S incendiary and phosphorus bombs on Azovstal, that an official said burn at temperatures of over 2,000 degrees Celsius.
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'The Russian military themselves claim that 9M22S incendiary shells with thermite layers were used,' said the Ukrainians.

'The combustion temperature is about 2,000 to 2,500 degrees Celsius. It is almost impossible to stop the burning,' Petr Andryushchenko, an adviser to the mayor of Mariupol, said on Sunday.