"We stayed in a cellar for a month. All the children had some kind of infection. They had temperatures, they were vomiting. They had to drink water from springs. They were sick and scared."
Mariupol has become a symbol of the brutality, resistance and creeping Russian gains of the war in Ukraine. For weeks, Ukrainian fighters held out in the Azovstal steelworks until Russian forces took control of the city. A once-bustling port city of around 500,000 people, after weeks of bombardment Mariupol has now been reduced almost to rubble.
Many civilians remained trapped in the city during the siege and spent weeks sheltering in basements. When they emerged, the situation in Mariupol was so desperate that some turned to Russia - the country which had bombed them out of their homes - for help.
Natalia spoke to ITV News by phone from a sanatorium in the Moscow region.
She did not want to provide her real name or exact location for safety reasons. Born and raised in Mariupol, she said she survived the bombing but finally left the city on June 1 to find medical care for her eight-year-old epileptic son. Before leaving, she spent more than a month living in a basement.
Natalia and her children lives in a basement with other Ukrainians for a month
"It was -10 degrees. We had no electricity, no water, no gas, no communications, no nothing," she said.
"There were many of us there. Me, my son and daughter all went to the basement after a (Russian) grad rocket hit our bedroom window on 10 March. There was smashed glass under our feet. We got out fractions of a second before everything caught fire."
Despite being forced out of her home by Russian airstrikes, Natalia said she refused to flee the city via humanitarian corridors because they were subject to frequent attacks. The only remaining option, she said, was to live underground.
Soon, the group of people living in the basement grew as it became too dangerous for people to remain in their own homes.
As the days turned from March to April and Russian forces got closer, the fighting intensified.
"At first there was tank fighting, shooting and then airstrikes. I saw with my own eyes how a 14-story building collapsed leaving only two floors. At this point, there were Russian soldiers there and they had entered the courtyard.
"Then there was a strike and the building was on fire. I saw there was still someone inside and started shouting. A guy ran towards a woman and stretched out his hand but she didn’t take it. She was then engulfed and burned alive."
No-one was spared the horrors of the assault on Mariupol, not even children.
"My children didn’t go outside at all. They were so scared. It was so cold in the cellar but they stayed there, even when there was sunshine outside and it was more or less ‘quiet.’"
In temperatures which were regularly well below zero, Natalia told ITV News the adults and children tried to stay warm by wrapping themselves up in whatever clothes and blankets they could salvage from the nearby flats. There were no medicines and many people were sick. Food was rationed to conserve supplies.
The occupants of the basement, from pensioners to small children, were crammed next to each other with no privacy, no toilets and no water. They sang songs and read books by torchlight to keep themselves entertained during the long days and nights of darkness.
When they emerged after living underground for more than a month, it was to a city they did not recognise.
Buildings had been destroyed or hollowed out by bombing. Flats in the once-prosperous centre of Mariupol with their twisted balconies, shattered glass and burn marks stood as a physical reminder of the consequences of a Russian scorched earth policy which reduced the city to a shell of its former self.
"When we came out, the Russian soldiers were there. They went around all the remaining flats doing ‘cleaning.’ They were searching for Ukrainian soldiers," Natalia said.
The Kremlin insists Vladimir Putin’s 'special military operation' is aimed at protecting "peaceful citizens." Russian state television frequently shows volunteers and the Russian military handing out boxes of humanitarian aid to Ukrainians in newly captured territories. Some Russians say they have even been ordered by their employers to donate to the humanitarian effort.
In Mariupol, people were given boxes with the Z sign in the orange and black colours of the St George’s ribbon, a Russian symbol which has become synonymous with the war in Ukraine.
"On the box were written the words ‘We don’t abandon our own,’" Natalia told ITV News.
The box contained flour, condensed milk, sugar and pasta as well as some tinned foods and hygiene products. There was not enough to feed a family of three people.
"They gave us a box for just one person. They said those were the rules. They told us, ‘you can come back in a week and get another box.’
"It felt very difficult," Natalia said in a quiet voice when she was asked how she felt about receiving aid from the country which had destroyed her home.
"It gets to the point, when you stand in a queue of more than a thousand people waiting for humanitarian aid, that you don’t think about anything anymore.
"People think all of us who stayed in Mariupol are traitors to Ukraine because we accepted humanitarian aid. But no one thought about how we didn’t have anything to feed our children.
"I felt the worst when they brought bread to our courtyard, and my child stood in a queue for bread," she continued, her voice breaking.
"I didn’t cry for the whole war but then I cried a lot. I used to be able to provide my children with everything, and now I can’t even provide them with bread."
Having survived the bombardment and fall of Mariupol to Russia, Natalia told ITV News she had no choice but to ask for Russian help when her eight-year-old son with epilepsy became ill.
"He had seizures, was not stable and there were no doctors left in Mariupol.
I was worried about my child’s life, so I wrote a letter to the head of the (Russian-backed separatist region) Donetsk People’s Republic."
To get treatment for her son, Natalia said she had to be "filtered." Russian forces have been reported to use 'filtration camps' to interrogate Ukrainians who remain in Russian occupied territory or who want to leave it.
In a village outside Mariupol, Natalia said she was questioned in a camp of several tents, guarded by Russian soldiers with guns. She was shepherded past four Russians who asked her questions, took her personal data and photographed her.
"They asked ‘what do you think of the authorities?’ ‘do you know anyone in the Ukrainian army?’" Natalia said she had already been warned by those who had been filtered before her to give "neutral" answers which would not elicit further questions.
In the camp, the city’s residents were forced to hand over their mobile phones. People who had reset their phones to factory settings were taken away for further questioning. After Natalia’s phone was returned to her, she said she received a notification which indicated her contact information had been externally downloaded - Russian forces were hoovering up Ukrainians’ personal data.
According to Natalia, everyone over the age of 18 in Mariupol was taken to the camp for questioning, even if they did not want to leave the city. Some were undressed as the Russians looked for tattoos, such as the flower of Ukraine, which might identify them as being pro-Ukrainian.
Once Natalia had been "filtered," she was handed a piece of paper.
"I asked ‘what is this,’ and they told me, ‘your ticket to a happy life!’"
The journey from Mariupol to the Moscow region on a bus full of other women and children took three days.
In a sanatorium in an undisclosed location not far from the Russian capital, Natalia said she had finally been able to get her son the medical treatment he needs to manage his epilepsy. What she has not been able to treat are his, or her, mental scars caused by months of war.
"He is still afraid of planes. He’s 8 years old but now behaves like an adult.
"Our task was to survive. No one cared about the people, the children, the elderly. People were just being shelled."
Born in the Soviet Union and raised in Ukraine, Natalia said she soon planned to return to Mariupol to live under Russian control.
It is, she said, something she does not "really want to think about.
"It’s the 21st century and it should be possible to talk. Two countries are responsible for what happened in Mariupol. The Russians bombed the city. The Ukrainians did nothing to evacuate it."
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When Natalia returns to Mariupol, it will not be to the flat where she cooked her children’s dinners or helped them with their homework. That flat, like most of the city, has been destroyed by shelling. She knows as autumn comes and winter falls it will be impossible to stay unless there is heating. The city’s water system has been badly damaged and there are warnings of major disease outbreaks.
But for Natalia, who feels abandoned by everyone and needed by no one, the only place she wants to be is Mariupol.
"I just want to live in my city. I was born there; my children were born there. I don’t care who the authorities are. I just want to go home."