“The liberation of Izium would be the most significant Ukrainian military achievement since winning the Battle of Kyiv in March,” the Institute for the Study of the War (ISW) said in its situation analysis on Sunday.

For some Izium residents, the sight of Ukrainian soldiers sparked waves of emotion.

“We welcomed them with tears in our eyes. We had been waiting for them for months … we are very happy,” 61-year-old Nadiya Nesolena says.

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Izium, in the Kharkiv region with a pre-war population of 50,000, had been fully occupied by Russian troops since April and had become a key logistics base for Moscow.

Life in the city was “very difficult” under the Russians, Nadiya says, recalling constant shelling, cold and hunger.

But she says she was one of the fortunate few, “lucky enough to have a house with a basement and some food”.

Signs of Russia’s occupation abound in Izium.

Plumes of white smoke rose over the roofs of the city, from ongoing fire at the ammunition depot that exploded Saturday as Russian troops fled.

Izium’s city hall, now adorned triumphantly with the Ukrainian flag, is battle scarred like so many buildings in the city: houses, residential blocks, shops, two bridges, and a school and a religious building, all destroyed.

Still dotting the city are huge signboards with Russian flags saying “We are Russia, one united nation”.

The Ukrainian soldiers, busy securing the area, still haven’t had time to take them down.

Back on the hill near the cell tower, 64-year-old Yuriy Kurotshka is stunned with joy that his city is back in Ukrainian hands.

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“All bad things eventually come to an end,” he says.

He was trying to reach his family who left for Kyiv in March, when Russian troops first entered the city.

Yuriy has a message for the Ukrainian army: “Please never leave, don’t hand us over to those Russians!”

Grygoriy Pyvovar, 61, who wanders through the quasi-empty city with his 16-year-old son Kyrylo, recounts how he met soldiers arriving in Izium on Sunday.

“We had tears in our eyes. We were so happy to see that our guys had come here!” Grygoriy says.

“We didn’t expect it would happen so quickly.”

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But the Ukrainian troops were not welcome back by all.

Many residents say that their pro-Russian neighbours took the road towards the Moscow-controlled east even before Russian troops evacuated.

Moscow says several thousand people have crossed over to Russia from the Kharkiv region.

Around Izium, abandoned Russian armoured vehicles were being towed by Ukrainian military trucks on Monday.

Ukrainian army convoys roamed the area, as footsoldiers march by or set up camp in the city’s periphery.

Several dozen broken-down Russian vehicles – branded ‘Z’, the symbol of the invasion – were lying on the side of the road.

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Alongside them, burnt trees, craters, shrapnel and unexploded munitions completed the picture.

In a small newly-liberated town near Izium, soldiers have piled up ammunition left behind by the Russians.

“We’re certainly planning on ‘sending’ all this ammunition back to them as a gift by air,” laughs a soldier nicknamed “Tank” who is busy securing bombs left behind.

There is also Russian food, but Tank jokes that his group “won’t eat that, it’s not good”.

Tank and his colleagues arrived early on Sunday to carry out demining operations and to disarm the traps they say Russian soldiers left behind.

Another group of soldiers passes by, saying they’ll have to come back later: they found a T72 Russian tank near the exit of the village, but it’s out of battery.

Additional reporting by dpa