The first disturbing sounds of explosions could be heard on the outskirts of the city of Kupyansk.
A small line of weary locals lined up to get water from a local well, each holding a collection of plastic bottles as there is no running water or electricity.
They barely flinched as the rumble of outgoing fire from the Ukrainian side reverberated around them, followed by the crackle of a shell landing further into the town.
“It’s scary,” said one woman, Vira, 72. “Of course we are afraid.”
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Ukrainian forces are trying to retake this city in a major counter-offensive in the northeastern Kharkiv region that has retaken swaths of land from Russian control.
But unlike other newly liberated areas such as the town of Izyum and the major city of Balakliya, Russian forces did not leave Kupiansk without a fight.
This turned the city into a front line, with Russia shelling Ukrainian positions, apparently from outside the eastern perimeter, and Ukraine using return fire to push them back further.
Central Kupiansk looks and sounds like a war zone, with burnt and shattered buildings, twisted metal and chunks of concrete littering the streets, and the few wandering residents having to deal with the fairly steady sound of incoming and outgoing gunfire.
Two women emerged from the basement of a building on a broken street.
One of them agreed to speak. She was visibly angry and blamed the Ukrainian side for the destruction, not mentioning the role played by Russian forces – an indication perhaps that not everyone in the city opposed the occupation of several months by Russia.
“How do we live? Take a look. No job, no money, nothing,” she said, waving her arms in devastation.
“Nothing to eat, no electricity, no water, no gas. I haven’t washed my hair for two weeks.”
The woman, sarcastically, added: “How do we live? We used to dream about this life our whole lives… It sucks.”
Ukraine’s operation to recover all parts of the Kharkiv region under Russian control officially began on September 6, targeting Russian positions in occupied areas.
Kupyansk is a rail hub, with tracks leading south-east to Donbass – a focal point of the Russian invasion – and also into Russia.
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Control of the city had given Russian forces the ability to more easily resupply front-line forces in the Donetsk and Luhansk regions, which include Donbass.
This made the reconquest of the place all the more important, strategically, for the Ukrainians.
Residents of Kupyansk said the period from September 9 to 12 was particularly “noisy and scary” in their town as the Ukrainians attacked.
“There was a lot of shelling from the Ukrainian side, jets were flying,” said Olena Dmitrieva, 55, who lives in an apartment building on a grassy, elevated area on the outskirts of town, but with a view of the center.
“I live on the fourth floor and these jets, these explosions, it was hell. Our building was shaking… We thought it was going to collapse now.”
She said her children and grandchildren lived east of Kupyansk, closer to the Russian lines, and it was not possible for her to visit them.
“God, why are we being punished like this?” she asked crying.
The Kharkiv region governor said Russian shelling in Kupyansk on Wednesday injured five people, including a 13-year-old boy.
Despite the active fighting, Ukrainian police and prosecutors are already on the ground in the city, gathering evidence of alleged Russian war crimes during the occupation.
Oleksandr Sirenko, deputy prosecutor of Kupyansk, went to the main police station on Wednesday.
A Russian flag was strewn on the ground near the entrance, along with a broken Russian police sign – indicators of who had used the building.
Inside, there was an eerie painting on one wall of a letter “Z” – an emblem of the occupation.
Investigators were searching a number of filthy cells where people appeared to have been held in cramped and filthy conditions. There was also a room that would have been used for interrogations where forensic experts collected DNA samples.
All the while they had to be alert to the threat of Russian attacks.
We were told to take cover if we heard the buzz of a drone, as it could very well be a Russian drone, searching for targets on the ground for the artillery guns to strike.
“It’s tough,” the assistant district attorney said of having to work in a war zone.
“But more difficult than being near the front line is being without electricity or light. It complicates our investigation. But we are collecting evidence on how Russia treated people. That’s where that there were assaults.”