It's autumn 1992, and an icy chill has settled over Sarajevo. Bosnian residents are struggling to keep warm in their besieged city, scavenging whatever firewood they can after gas and electric supplies have been cut off. From their hiding spots in the hills surrounding the town, snipers shoot at anything that moves.

AFP photographer Patrick Baz, newly arrived on the scene, shoots a picture on October 27, 1992, about six months after the start of the siege of Sarajevo, which would last another three years and become the longest such assault in modern times. More than 10,000 people would lose their lives.

That image -- of a gaunt young man hauling wood -- could easily have stayed tucked away in the agency's archives forever. But thanks to a series of coincidences it has, twenty years later, taken on a new life of its own.

"I chose Patrick's shot to use in the 20-years-on feature to illustrate the shortages in the city," recalls BBC journalist Adrian Brown, explaining why he included it a multimedia project on the 20th anniversary of the siege. "This young boy's look of anguish really caught my attention."

A few months after Brown's piece was published online, Vladimir Vrnoga, a former Bosnian refugee who's been living in California for more than 17 years, was tapping away at his computer when his phone rang. "Drop whatever you are doing," a friend said. "Check out this Web page."

Vladimir couldn't believe his eyes.

"I had a shock. Seeing that picture brought a flashback of the moment when it was taken. Suddenly, 20 years later, I was back in Sarajevo during the war," he says by phone. "I could smell the dampness of the air, felt the blisters on my hands from chopping the wood with a meat cleaver -- and that was barely the beginning of the siege."

Vladimir was 17 at the time. A Catholic with a Croatian father and a Serbian mother, his family illustrated the inter-communal harmony that existed in Sarajevo before the war. He had just registered at the University of Sarajevo to study veterinary medicine.

But the bloody conflict turned his plans, and his life, upside down.

-- Picture 'represents all the suffering' --

"This picture represents all the suffering we went through," Vladimir says. "At night time, the temperatures dropped really low. We had to collect wood to heat our home and survive. The only thing we had to eat was rice. The snipers were everywhere above us. They were shooting at everything. They were shooting children. They were shooting cats."

Vladimir had to drop his studies, and was pressured to enlist in the Bosnian army. Months of fighting, suffering and exhausting marches followed. He lost 15 kilos (33 pounds) in just three weeks after joining up.

He finished his service at the end of 1994 but was called up again just a few days later. This time, he and his mother, Milena, left for Croatia and then for Austria where they spent five months in a refugee camp. They finally departed for the United States in April 1995.

Mother and son moved to Chico, north of San Francisco in California. The wood collector-turned-refugee, today 38 and married with a three-year-old daughter, now works at a large brewery.

Vladimir has never returned to Bosnia.

After the initial shock of seeing himself in the photo wore off, he contacted the BBC journalist, who put him in touch with Patrick. The photographer and his subject, who had until then been unaware of each other's identity, swapped emails and hope to meet one day.

"I remember very well the day the picture was taken. I was walking and saw the photographer at the side of the road. We exchanged some words, I asked him for a cigarette. Then we both continued our way," Vladimir says.

Patrick, who is now AFP's photo director for the Middle East and North Africa, has a vague memory of shooting the photo. "I'd only been in Sarajevo for a few days," he recalls. "I didn't know where to go. While I was heading for the front line, in the mountains, I came across these guys. That's about all I remember."

But the chance reconnection between the two has stirred up powerful memories for the Lebanese photographer, who grew up in the middle of a civil war before leaving to take photos for AFP in conflicts across the globe.

"In my career, there are two conflicts that stand out for me," he says. "One is Somalia, a country where you could get killed for your wristwatch -- they don't even ask you for it, they just kill you. The other is Sarajevo."

In the autumn of 1992, Patrick and AFP reporter Patrick Rahir arrived in the Bosnian capital after travelling from Paris in an armoured car the agency had bought to cover the conflict.

-- 'Welcome to Hell' --

"Arriving in the town was shocking," he says. "We'd started by travelling through bucolic Serbian villages, where everything seemed normal. Then at one point, we crossed a graffiti-covered bridge where someone had scrawled 'Welcome to Hell' on a wall. From then on, we were in a nightmare."

"Upon arriving in Sarajevo, it felt a little like the Lebanon of my youth. But in Lebanon, war was my daily existence, I didn't think about it. Here, I arrived with more of an awareness. And in Beirut, even during the darkest times, we could always leave the city and find a peaceful place.

"But Sarajevo was a deathtrap. A modern city where people had nothing to eat and no way of keeping warm. Snipers shot people as they headed to the bakery. In Syria and other war zones, people come up with strategies to thwart the snipers, like hanging black sheets across roads to block a shooter's view. There was nothing like that in Sarajevo."

Just as for Vladimir, the Bosnian winter's biting cold remains etched into the photographer's memory.