At first sight, the city appears to be almost deserted.

But underground, in cellars, garages and depots hidden from sight, Stepanakert, the capital of Nagorno-Karabakh is fully mobilised to support troops fighting Azerbaijani forces at the front.

As air raid sirens sound for several minutes, warning of the next salvo of rockets or a the imminent arrival of drones, a textiles factory tucked into the side of mountains that dominate the city is quietly at work.

In a storeroom are boxes of supplies for the frontline soldiers: coffee, chocolate and cigarettes
In a storeroom are boxes of supplies for the frontline soldiers: coffee, chocolate and cigarettes AFP / ARIS MESSINIS

A few cars are parked nearby, indicating some activity. Men in civilian clothes -- sometimes with a parka or camouflage trousers -- and others in full uniform are coming and going as discreetly as possible.

To a casual observer, the building might seem to be lying idle. But while the upper floors are empty, people are working hard in the vast basement.

First-aid workers and nurses are busy cleaning khaki stretchers, presumably to evacuate wounded fighters. The litters are stowed away in four old Soviet-era UAZ vans from the local emergency services, ready to leave for the front.

Some volunteers barely knew how to sew when they arrived
Some volunteers barely knew how to sew when they arrived AFP / ARIS MESSINIS

In a storeroom, dozens of boxes are piled up: coffee, bars of chocolate, cigarettes and other supplies collected in the Armenian capital Yerevan and other cities, destined for front-line soldiers.

Lying on the ground are dozens of pickaxe handles, brand-new shovels still in their wrapping, vital tools for positions where sandbags must be filled for protection.

Further inside, in a large neon-lit hangar, about 10 people are busy behind two rows of sewing machines.

They used to work on the upper floors, says Sanasar Tevonyan, using a ruler and pencil to trace a pattern on green camouflage fabric.

The basement production line now produces uniforms, sleeping bags and ammunition belts
The basement production line now produces uniforms, sleeping bags and ammunition belts AFP / ARIS MESSINIS

"We came down to the basement a week ago to take shelter from the bombs that were starting to rain down."

Everyone has a loved one fighting at the front, they say
Everyone has a loved one fighting at the front, they say AFP / ARIS MESSINIS

Sanasar, 62, said he had come from Russia to fight, but was considered too old. "Here, I can make myself useful."

Before the conflict started, the factory produced yarn for carpets or jackets that were exported to Italy.

It has been converted to producing uniforms, sleeping bags and ammunition belts, helped by volunteers devoted to the cause of "Artsakh" the Armenia term for Nagorno-Karabakh and the official term for the self-proclaimed breakaway republic, which is recognised by no country, not even Armenia.

After years of conflict, many people in this ethnic-Armenian region of Azerbaijan have joined the cause, each one helping the fighters who battle Azerbaijan as best they can.

Some factory staff preferred to evacuate with families over the border to Yerevan. Bella Hayeapetyan chose to stay.

Wrapped in a wool cardigan, spectacles perched on the end of her nose, she has no regrets, saying that she remained "for our sons, our brothers, our husbands fighting on the front."

A few younger volunteers do their best at the sewing machines.

"Some of them didn't know anything," she says. "I taught them to sew."

One is Maria Miqayelyan, 36, who with her colourful leggings looks like she would be more at home at a zumba class. Today however, she is busy embroidering the pockets of an ammo jacket.

"This is a small country," she says. "Every family has someone at the front. Everything we are doing, we are doing for our people and our country."

"There isn't a family that doesn't do something, one way or another, for the war," effort she adds. And frontline fighting is just 30 kilometres (20 miles) away.

They work all day, sometimes until midnight. Some sleep on site, on camp beds. And every day, vehicles come from the front to collect the material produced here.

"We all have a loved one at war, and whoever defends our land at the front is our brother," Bella says defiantly.

Meanwhile, the sewing machine hums peacefully beneath her fingers.