Kateryna Kitrish was forced to watch on from afar as Russian troops surrounded her workplace, inching closer each day.
Ms Kitrish worked as engineer at the Azovstal Steel and Iron works complex for 16 years before she escaped Ukraine for Poland.
The sprawling dockside steelworks and its maze of underground passageways has become the last pocket of Ukrainian resistance in the southern port city of Mariupol.
"My father, husband and mother all worked there, and we were happy to be their workers," Ms Kitrish said.
"The city is dead now."
Moscow has said the entire city — apart from Azovstal — is now under Russian control.
Russian President Vladimir Putin has claimed victory in Mariupol, despite continued resistance from an estimated 2,000 Ukrainian fighters holed up in the giant steel mill.
Mr Putin has ordered Russian troops not to storm the steelworks, but to blockade it "so that not even a fly comes through".
Ukrainian President Volodymyr Zelenskyy has said up to 1,000 civilians could also be sheltering there.
Watching her city and her workplace come under heavy bombardment has been devastating for Ms Kitrish.
"It's like you're killed but you're still alive ... some[thing] in your soul had died," she said.
'A city within a city'
Azovstal covers an area of almost 11 square kilometres and has a labyrinth of underground tunnels stretching 24 kilometres.
Ms Kitrish said the tunnels in Azovstal were built after World War II.
"They are very strong … These tunnels are for people to hide from bombs," she said.
Before the war, Ukrainian authorities prepared for the Russian offensive by building up stockpiles of food and water at Azovstal.
Earlier this week, Moscow had predicted the steelworks could fall within hours.
Commanders of Ukrainian units at the plant made a series of desperate video appeals in recent days, saying they were clinging by a thread, and begging for help.
Major Serhiy Volynskyy of the 36th Marine Brigade said in a video earlier this week that "the enemy outnumbers us 10-1".
"We are probably facing our last days, if not hours," he said.
But the complex layout of the plant has helped Ukrainian forces, and could draw out the fighting further.
Ukrainian military expert Oleh Zhdanov said the area would be "very hard to storm" and Russia risked losing troops there.
Steelworks bomb shelters braced for attack
Former employee Artem Papu Gennadievich, 35, worked at the Azovstal plant for 14 years, starting out as a crane operator and becoming an equipment reliability engineer.
He told the ABC the tunnels can accommodate thousands of people, while Metinvest, the company that owns the mill, has said 4,000 can be housed there and shelters were stocked with enough food and water to last three weeks.
Mr Gennadievich said the plant had been bracing for a situation like this since Russia's annexation of Crimea in 2014, when Russian-backed separatists tried to take Mariupol.
He added that bomb shelters were equipped with basic necessities such as beds, chairs and toilets.
"There were food supplies, equipment for ventilation, lighting, water supply was prepared, and heat-resistant doors were installed," he said.
"Each workshop has a large network of these tunnels, there are maps ... since there is a chance of getting lost."
Mr Gennadievich said Azovstal's location — surrounded by sea on one side — and size might be a reason it had become the site of the last battle.
Mariupol is a key strategic target for Russia. Capturing it would not only deprive Ukraine of an important port and resources, but would form an uninterrupted land corridor of Russian control from Crimea to Donbas.
Mr Gennadievich moved to Alaska last year, and like Ms Kitrish, he has been unable to connect with those holed up inside Azovstal.
But he recognised an old friend from the plant in a video posted to Facebook this week. The man appeared to be sheltering with his wife, son and daughter inside a converter workshop inside Azovstal.
"I made sure that my friend is alive, thank God," he said.
"I don't know how life goes on there, and I don't think anyone knows because they don't have a mobile connection.
"I also understand what a difficult situation [it] is now in the city, and that it is very dangerous to be there.
"Anything can happen ... it's scary."
Besieged city
Ms Kitrish knows that all too well.
From the start of March, she and many of her colleagues were unable to work due to the ongoing shelling of the city, where power and water had been cut off.
"I had to flee because my apartment was destroyed by a rocket," she said.
She hopes to travel to the United Kingdom with her two sons and find work there, but her husband remains in Mariupol.
Her husband's son from a previous marriage was killed in a Russian rocket attack in early March, she said.
"The doctors could do nothing," she recalled.
Ukrainian officials estimate 21,000 civilians have died in Mariupol, and new satellite images from a nearby town appeared to show more than 200 fresh graves.
Ms Kitrish's mother, who is caring for her grandparents, cannot leave either, she said.
She hasn't been able to contact her mother for more than a month, since March 13.
"I actually know nothing about my mother. I hope she is alive, I hope she is OK," she said.
ABC/AP
