May 14, 2007. A sudden explosion of pain in my back pushed me to my knees. In Nuristan, northeastern Afghanistan, surrounded by US soldiers fighting for their lives in an Al-Qaeda ambush, I'd been shot.

I'd wanted to be ”outside the wire”, living with the soldiers on the front line. My request had initially been greeted with amazement. Was I aware of the dangers I would be exposing myself to? But I wanted to show life in a combat zone.

I had to go through the soldier experience.

After months of negotiation, the army agreed.

The battle continued for about an hour after I'd been shot. Kneeling behind a Humvee, I was still exposed to whoever had just shot me. I ran and dived behind a large rock. As I curled into a ball, another bullet slammed into the rock, two inches above my head. It appeared the sniper wasn't finished with me yet.

An explosion ripped through the air, as a rocket-propelled grenade detonated against the Humvee I had just abandoned. Close by, three soldiers crouched behind some more rocks. Bullets hammered their protective boulders. Staff Sergeant Anderson was putting a field dressing on Sergeant Clark's arm; moments before he had also been shot. Staff Sergeant Sears was shouting, telling me to hang in there. He asked me how many times I'd been hit, where I'd been hit. His other questions blurred into one another.

That morning I'd woken to the sound of helicopters buzzing low overhead. A couple of Black Hawks disappeared over the mountains to the west, and within minutes, two troop-carrying Chinooks appeared, with an Apache gunship escort. This is a volatile area, where the US presence is only months old, and where fighting is fierce. In the foothills of the Hindu Kush, with peaks rising to over 18,000ft, Nuristan is also where experts believe Osama bin Laden's last two propaganda videos were recorded.

All over the small outpost, soldiers made final preparations for the day's mission. It was a simple operation, planned to take several days, and the idea was to isolate the insurgents. But as soon as the American and Afghan troops positioned themselves, everything changed. Radio reports came in of a TIC, or ”troops in contact”, the army's newest euphemism for a fight. But it was not the fight we expected. It turned out to be an ambush 20 kilometres away.

Listening to radio transmissions from a TIC is an awful experience. When a ”Break, break, break” call goes out, then a ”Nine-Line” request, things are at their worst. ”Break, break, break” indicates that an emergency message is about to be broadcast and that all other callers should cease transmitting. A ”Nine-Line” informs all listeners that a US soldier is wounded and in need of an immediate medical evacuation We were now listening to multiple calls for medevac, meaning there had been both US and Afghan personnel involved.

Radio reports kept coming in. Then came the worst news of all. While most troops had pushed out of the kill zone and back to their base at Kamu to get their wounded onto helicopters, up to 10 Afghan soldiers had been left behind. It was unclear how this had happened, but the most likely scenario was that they jumped clear of their vehicles, which were then damaged during the attack. Several Afghans had been killed; if the chain of command was broken, it was possible that someone could have been left behind.

Within minutes we were in a Humvee, racing towards the ambush. We stopped by an old bridge and climbed out of the vehicle. We'd parked in the shade of some trees — if the insurgents couldn't see us, it would be harder to shoot at us. Then, as if on cue, the insurgents on the south side opened fire. They could see us, so we ran around to the north of the Humvee. Up top, the .50-calibre machinegunner was pouring withering fire on the southern ridge. We saw Master Sergeant Best and Sergeant Clark running towards us. Everyone laid down fire to cover them, while I shot photographs of their dash over open ground.

By now the protective gunships had left us as they were low on fuel. As soon as they left, the attack intensified. This is a classic tactic of guerrilla fighters. They'll hit, then hide and wait until the gunships have to leave. Placing the dead and wounded on the road, along with sensitive items such as radios, is another favoured tactic. It draws rescuers into the kill zone.

Bullets were still flying through the air too close for comfort when a US marine got out of the Humvee. He greeted Best like an old friend: ”Good to see you, man, I'm your replacement.” Then he turned to me, grabbed me and pulled me close, so I could hear over the gunfire: ”Man, you're f***ing crazy. Nobody could be paying you enough to be here right now.” Little did he know that nobody was paying me at all.

Strangely, the initial pain of the sniper bullet hadn't been that bad, but I knew as the shock started to wear off the pain would get worse.

Lying behind that rock I felt more alone than ever in my life. I thought about my girlfriend, Helen, back in London, hoping I'd see her again. As the pain got worse, fear grew over the extent of my injury. Briefly, I wished I'd died straight out from the shot, but I pushed that thought away and decided I was not going to give up. I was going to live and get these photographs published. I was going to tell this story, and I was going to see my family and Helen again. I think I was behind that rock for 10 or 15 minutes before they got to me. They ripped open my shirt, and I heard them say I'd been shot in the kidney.

I managed to hold on to both of my cameras, which felt heavier than ever. I was terrified I'd be shot again — I couldn't tell if the firing around me was outgoing, or if we were still being shot at. I was moved towards a Humvee, my left arm behind my back, trying to hold the dressing in place and keep pressure on the wound. It hurt like hell, and my arm felt weak. More bullets hit my side of the Humvee. Clark was talking to me, and I was struggling to focus. ”Stay awake, stay alive,” he kept saying. He asked me about home, Helen, anything that would keep me awake — and he had his own wound in the forearm.

Finally we were on our way, but it was a trek back to the Kamu outpost. We were driving over the worst roads in the world, and every time we went over a hump I would involuntarily moan. After a drive that seemed to take eons, but was about 20 minutes, we arrived back at Kamu. When we drove through the gates it was chaos. As we stopped, several soldiers ran to the Humvee. A medic, Specialist Cerezo, helped me out, and got me face-down on a stretcher. I was light-headed. I think I'd had some morphine. But I came back to reality when I heard someone say: ”Put those two with the other dead bodies.” My God, I thought, how many are dead?

Some of the guys I had befriended over the previous weeks came to talk to me. There was a lot of concern on their faces, but the banter was light-hearted. I asked them to take pictures of me, which they weren't comfortable with, but I insisted. The deal was, if one of them got hurt I wouldn't hesitate to photograph the scene, and so, quid pro quo, they should photograph me.

I asked how many people had been hurt. The current figures were 15 dead from the Afghan National Army (which rose to 17), four wounded and one missing in action, believed captured by the insurgents. God, or Allah, help him, I thought. As for US personnel, there were seven wounded. These were shocking figures. Apparently, I was the worst, and so I would be going out on the first bird.

John D McHugh was airlifted out of Nuristan and flown to an American military hospital where he underwent emergency surgery; the insurgent's bullet had entered the left side of his chest, just missing his heart, and had torn open his colon, diaphragm and spleen before exiting his back, causing a wound the size of a hand. He was flown to a military base in Germany for further treatment before returning to London, where he is now recuperating. Earlier this month, surgeons reversed the emergency colostomy he was given after the ambush. McHugh has vowed to return to Afghanistan.

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