In six months of Russian occupation and eight months of fighting, Izyum Hospital in eastern Ukraine never stopped working, operating on wounded civilians in its basement while awaiting liberation.

This small but strategic city in the Kharkiv region was captured by Moscow in March and fully occupied a month later.

Its recapture by Ukrainian troops on September 11 was a strategic victory for Kyiv, although the population has shrunk from around 46,000 before the war to around 8,000 or 9,000.

Since then, the hospital has managed to regain some semblance of normalcy after being hooked up to a generator and workers gradually replacing broken windows.

In a heated, bleach-scented hallway on the first floor, a patient in his pajamas strolls past while a cleaner mops the floor and a secretary shuffles through admissions files.

“We have about 200 patients today, compared to 50 in June,” says Yuri Kuznetsov, a 52-year-old surgeon who heads the hospital.

“This is where our operating theater and intensive care unit used to be,” he says, pointing to the gaping hole and the destruction left by a rocket attack in March.

With a weary face, the doctor attributes his exhaustion to his night shift, not to the six months he spent every waking hour tending to the wounded in dirt and rubble, in front of the Russian occupying forces camped next door.

“The hardest time was starting[the cast]with so much uncertainty about what they were going to do to us,” he recalls.

Kuznetsov said there was “some fighting at the beginning” but the Russians let him continue to treat Ukrainian patients, assisted by a few nurses who stayed behind.

The Russian troops set up their own field hospital in a neighboring basement.

“They were right there, about 20 meters from my office,” says Kuznetsov, who spoke to them every day but says they never asked him to operate on wounded Russian soldiers.

“Doing our job wasn’t the hardest part, the hardest part was just staying alive,” he recalls of those dark days.

A few weeks after retaking the town of Izyum, Ukraine said it had discovered a mass grave in a nearby forest containing at least 450 bodies, most of which bore signs of a violent death.

Thirty of them showed “signs of torture,” regional officials said.

Since the beginning of the war, the hospital has lost two of its employees: a coroner who was shot dead and a doctor who died under the rubble of his own home.

As the city was ravaged by constant bombing, the hospital set up an emergency room in the basement, where stained stretchers served as operating tables among stacks of boxes and dirt.

“We lost patients because we didn’t have the right equipment and medicines, but by the grace of God we were able to limit the number of deaths,” he said.

One of those rescued was a man who sustained a gunshot wound to the abdomen.

“A few weeks ago, my office door opened and the man walked in and said, ‘Doctor, do you remember me? I’m alive!’” says Kuznetsov.

“We all had moments when we thought about escaping. We’ve all had breakdowns and bouts of depression,” he admits.

“But it’s moments like this and the solidarity of my colleagues that kept me here,” he smiles, looking forward to coming home and finally bowing his head to rest.