Devastating photos taken from the skies above Ukraine show entire neighbourhoods razed to the ground by Russian forces.
Images taken on Saturday by private US satellite firm Maxar showed fires burning in Mariupol and dozens of apartment buildings burnt to the ground.
Maxar confirmed fires were raging in the port city's western districts - where high-rise buildings were severely damaged by Russian bombing and shelling.
The Maxar pictures include a multispectral view of fires in an industrial area of the Primorsky district.
The images also reveal burning apartment buildings on Zelinskovo Street.
The United Nation's Office for the Coordination of Humanitarian Affairs said: "There are reports of looting and violent confrontations among civilians over what little basic supplies remain in the city.
"Medicines for life-threatening illnesses are quickly running out, hospitals are only partially functioning, and the food and water are in short supply."
On Friday, Mariupol City Council claimed at least 1,582 civilians had been slaughtered there as a result of Russian shelling.
These figures can't be independently verified at present.
Mariupol was one of several cities evacuated by Ukrainian authorities today.
At least 13,000 people in total - which is almost twice the number who managed to get out the previous day, said Deputy Prime Minister Iryna Vereshchuk.
This is almost twice the number who managed to get out the previous day.
Vereshchuk said in an online message that no one had managed to leave the besieged city of Mariupol and blamed obstruction by Russian forces.
Moscow had earlier accused Ukrainian forces of intentionally trapping people there.
Three people including a child were killed in a Russian strike on a maternity and children's hospital in the city of Mariupol, officials said.
Some 17 people were also injured, including staff and patients, local officials said.
The Mariupol city council said the strike had caused "colossal damage", and published footage showed burned out buildings, destroyed cars and a huge crater outside the hospital.