If the Russians seize the Azovstal industrial district, where the marines have been holed up, they would be in full control of Mariupol, the lynchpin between Russian-held areas to the west and east providing a land corridor for troops and supplies.
It would be the first major city to fall to Russian forces since they invaded Ukraine on February 24.
"Mariupol is still Ukrainian," the mayor of the besieged port city, Vadym Boychenko, said on Wednesday.
He added that 90 percent of the infrastructure in the city had been destroyed and the death toll could surpass 20,000.
That same day, Ukraine’s Azov battalion reported that a Russian drone had dropped a "poisonous substance" on troops and civilians in Mariupol, causing respiratory failure and neurological problems.
Halyna Pastushuk has this report.
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