The mayor of the Ukrainian port city of Mariupol said Monday his city was "in the hands of the occupiers" after a weekslong siege by Russian forces that flattened the city, left an unknown number of civilians dead and forced hundreds of thousands of people from their homes.

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Boichenko called for a complete evacuation of the remaining population of Mariupol, which had a population of over 400,000 before Russia launched its invasion of Ukraine on Feb. 24.

"According to our estimates, about 160,000 people are in the besieged city of Mariupol today, where it is impossible to live because there is no water, no electricity, no heat, no connection," he said. "And it's really scary."