'Sergeant, I thought you might want to do something about this.' Mase, the Royal Marine who had called me to join him in his sand-bagged sentry post, or 'sangar', was pointing towards the barbed-wire road block 100 yards north of our isolated compound in the Afghan outpost of Now Zad.
The road block was designed to prevent a suicide bomber driving into our walls. A small, white, terrified-looking dog was trapped in it. The dog had a wire noose around its neck.
Having broken free from whatever it had been tied to, it tried to run through our barrier, but the noose had caught on the barbed wire. The more it struggled, the tighter the noose became. The dog was slowly killing itself.
Puppy love: A trio of pups rescued by Royal Marine Sergeant Pen Farthing
The 100 yards that separated me from the dog was in no-man's-land. The obstacle was situated across the only 'real' road in this area of Helmand province, a single strip of tarmac that ran north to south for 400 yards.
At one time shops had lined the road. Now, there was no one to be seen, and the fronts of the empty stores were a mess of twisted metal and broken wood; their walls peppered with bullet holes.
The network of alleyways leading off the road was notorious as a hiding place for Taliban fighters.
I wondered why this was happening to me, but I knew I couldn't walk away. I squeezed through the narrow slit at the front of the sangar and on to the edge of the roof on which it was perched, then climbed down to the road.
Everything was eerily quiet.
My heart racing, I ran at a crouch up the centre of the road. As I got closer the dog started to fight to free itself again.
'Chill, dog, I'm on your side,' I called out. I was conscious of talking too loudly, but the dog was making enough noise as it was.
'Help me out here, fella, I don't want the Taliban to know I am here.'
I sliced through the strands of wire with my cutter. The dog was still pulling madly away from me and - as the last strand broke - it shot away. The wire loop was still around its neck, but I hoped that it would eventually work loose.
'No problem, buddy,' I said, watching it go.
Standing in the middle of a deserted street in the Taliban heartland was not a good idea. As swiftly as I could, I walked backwards towards the sentry post.
'Nice one, Sarge,' Mase said as I rolled head first in to the sangar.
'Let's keep this one quiet, eh?' I said as I dusted myself down. At 37 I was getting too old for this.
Things were getting out of hand. How on earth had I managed to become responsible for the welfare of every stray dog in Helmand?
I was a sergeant with Kilo Company 42 Commando Royal Marines, responsible for the 20 young lads who made up 5 Troop.
It was autumn 2006 and we were stationed in a mud-walled compound in a small market town which, at first sight, looked like something out of Monty Python's Life Of Brian. Nothing had changed in hundreds of years.
To the south, the flat expanse of the Afghan plain stretched into the distance. To the west, north and east, the mountains rose from the desert floor.
The town of Now Zad had been plagued by some of the worst fighting seen since the coalition forces removed the Taliban from power. It was a transit stop for Taliban fighters to resupply as they headed West towards other targets.
Pen with two of his charges, RPG and Jena
'Taliban Central' was an expanse of woods on the other side of a dry riverbed. The Taliban managed to keep us occupied nearly every day. They tended to hit us with mortars first thing in the morning or about half an hour before it got dark.
The howl of an incoming mortar as it arches across the sky sounds good only in the movies. In reality, it is as scary as hell.
There were no people living within 200 yards of our compound; it was too dangerous.
The compound was designated a 'safe' house. Precisely what was safe about a mud compound surrounded by armed religious fundamentalists who wanted to kill everybody inside was unclear.
It was a couple of weeks after arriving that I chanced upon a dogfight while on patrol outside the compound.
About 15 Afghans stood in a circle in an alleyway. Most were Afghan National Army soldiers, the rest were the Afghan National Police (ANP) members who shared our compound for their own protection.
The ANP were supposed to bring stability back to Afghanistan, but they were poorly paid and poorly trained. They weren't very popular, either.
I recognised some of this lot from two days before when I had caught them tying up with wire a dog they said they planned to enter into the 'Regional Dog-Fighting Championships'.
I secretly freed the dog later and it ran off to join the pack of at least 50 strays that prowled the perimeter of the camp at night searching for food.
This time the Afghans had long sticks that they were using to push and beat the two angry dogs inside the circle.
One hit the alley floor with a sickening thud. Its larger opponent landed next to it. Both dogs went for each other's throat. Both had bloodied stumps where their ears had been.
I had come to Afghanistan to help people get back on their feet, not to promote this kind of barbarism. I try to respect other cultures but after the earlier episode I was not about to take the diplomatic approach again.
My wife Lisa and I had two dogs back at home - Fizz Dog and Beamer Boy.
Fizz Dog, a rottweiler, came to us as a puppy from a breeder. We got Beamer, a black and white springer spaniel, from a rescue centre. He loved nothing more than floating around in the smelliest cattle trough he could find. Taking the dogs for walks on Dartmoor was how we relaxed.
So, as a dog lover, there was no way I was going to tolerate animal cruelty. Especially not while I had a big gun. I burst through the circle of men with such force that two of the soldiers were almost knocked over.
'What the hell's going on?' I screamed. The dogs bolted through the gap I had created and the Afghans surged towards me. The most senior policeman pushed me in the chest as he spat incomprehensible words.
Kilo Company on dawn patrol in Now Zad, Afghanistan
'Back off buddy,' I said, using the palm of my left hand to shove him. He landed in a heap on the floor. 'Don't touch me again.' Pointing at him, I raised my rifle.
As the Afghans screamed obscenities at me, Dave, one of our more experienced corporals, pushed into the throng to stand alongside me.
'Nice one, Pen,' he said. 'Time to leave.'
He led me back towards the patrol, which had closed ranks into the alley and stood facing the Afghans silently. The Afghans got the message.
Two days later I wandered over to a derelict building on the western side of our compound to see if I could find a use for it. I was surprised to hear a menacing growl.
My torch picked out an alsatian-type dog curled up in the corner. I recognised it as one of the dogs from the alley fight.
'The ANP let you in here, didn't they?' I whispered. I threw him one of the biscuits I carried with me. The dog sniffed it suspiciously then picked it up.
I pushed another one towards him but as my hand neared he gave a bark and lunged his head forward. I shot backwards, landing on my backside.
'OK, I get it. Your space,' I said. I gave him a bowl of water and the rest of the packet of biscuits. I didn't want to think about what the ANP had planned for him, but I had duties to carry out and had to leave him.
That night I was walking across the compound when I noticed the dog sitting outside the building.
He pushed off his rear legs with an unsteady jerk and wandered towards me. For a second I thought about running. The dog sniffed my trousers. I realised I was holding my breath.
I reached my hand down towards his head. It suddenly struck me that he had probably never been stroked before, but it was too late and my hand was next to his muzzle.
I let him sniff my hand a few times and then, unexpectedly, he sat down next to me. I stroked his head, standing in the glow of the Afghan moonlight.
I visited the dog in his derelict building every day. He would always bound up to see me. We were becoming mates and he allowed me to rub antiseptic cream into his ear stumps.
On the phone, I told my wife Lisa, a Royal Navy Wren, about the dog. I heard the sigh. 'You are not bringing home a dog from Afghanistan.'
'I know, but I have to do something for him. He's got no ears, Lisa.'
She promised to try to find an animal welfare organisation in Afghanistan that would rehome him.
In the meantime, I told the Officer Commanding of my plan to build a small, enclosed dog run. He didn't say 'Yes' but he didn't say 'No' either. I took that as permission.
Creature comforts: Pen and RPG take a break inside the Marines' compound
One of the lads suggested we called the dog Nowzad. 'The town is battle-scarred, right?' he said. 'Well, so is the dog.'
I found a building in the compound that had lost its roof and a wall and fenced it off to make a run. I left Nowzad there while I went off for radio watch.
When I came back, some of the lads had built Nowzad his very own mortar shelter from sandbags and plywood. I hoped he wouldn't need it, but that night the Taliban bombarded us for an hour and a half.
We returned fire and the noise was deafening, painfully so when an F18 dropped two 500lb bombs on the Taliban positions.
A wave of air radiated outwards from ground zero and hit our position with an audible oomph that caused the wooden roof to shake. The boom vibrated around the mountains as it faded to nothing.
After about half an hour of silence, we realised the Taliban had fled.
I jogged round to Nowzad's run, but he was nowhere to be found - somehow he had scrambled over the 5ft fence.
Nowzad still didn't get on too well with strangers and the last thing I needed was him to bite somebody as he roamed around the compound.
I bumped into Dan, the lad who had named Nowzad, just as he ran out of the entrance to the living area. 'Come and see this, Sergeant,' he said.
I followed him over to one of the cell doorways. Dan pointed under a bed. There was Nowzad curled into a ball, eyes wide.
'Halfway through the contact he barged in here,' Dan explained. 'He just looked at us and then squeezed under the bed.'
Nowzad had never been over this side of the compound yet he had found his way to safety, just one room away from where I slept. 'It's OK now,' I said, comforting him. 'I'll get you somewhere safe, just give me time.'
A few of the lads started visiting Nowzad during their downtime. They enjoyed feeding him biscuits, even though they took care to remain on the safe side of the run. I struck a deal with the ANP to 'buy' him in exchange for some torch batteries.
When I was up in the early hours, I let him have the run of the compound. He would spend the first few minutes chasing me around.
For those rare moments he would be like any other socialised dog and, for me, all thoughts of being in the most dangerous place on Earth vanished.
One night, on the way to see Nowzad, a dog ran out of the shadows at me. It darted from side to side as it crossed the 30 yards between us in a series of zigzags. He threw himself down on the ground in front of me, eagerly watching me.
He wasn't a fighting dog - he wasn't big enough and he was still in possession of a pair of floppy ears.
Meet the pack: Pen ended up caring for five dogs and 14 puppies.
They included AK, who was rescued after being bitten by a snake
I reached out my hand. The dog spun twice on the spot, kicking up a dust cloud. When I took a pace towards him, he charged full pace towards me, before veering off at the last moment.
'Mad as a box of rabbits,' I said. I guessed he had dug his way under one of the compound gates. As I walked over to Nowzad's run, the small dog followed. Without thinking, I let Nowzad out.
He charged straight for the newcomer, but then simply stopped and started sniffing the smaller dog. Amazingly, they began playing together.
As usual, Nowzad didn't want playtime to end and it was a struggle to coax him back into the run.
When I'd succeeded, I turned to the young dog. 'You get a reprieve,' I said. 'I haven't got time to get you out the gate now.'
I headed off for my radio watch and the dog followed me to the ops room door. 'Sorry, buddy, you can't come in here,' I said, closing the door behind me. Hours later, I opened the door to find the playful dog curled up in front of it.
As soon as I bent down to stroke him, he jumped up, instantly awake.
'Sorry, but you'll have to leave,' I told him. 'I can't have the boss seeing you running around.' It took me the best part of an hour to coax him out of the compound.
The next day, the dog was back. Again he darted out at me when I was on my way to see Nowzad.
The way he ran in random line reminded me of a rocket-propelled grenade. 'RPG, that's a good name,' I thought to myself.
I opened the gate for Nowzad and he charged out to see his friend. As I watched them playing, I made my mind up. RPG was going to be given the same chance as Nowzad. He joined my improvised dog pound.
The next time I spoke to Lisa, I waited until there was a pause in the conversation and then went for broke. 'If we are trying to rescue one dog, why not two?' I asked.
She didn't sound that chuffed and she wasn't making much progress finding a rescue centre, but she said she would keep trying.
A few nights later, barking roused me from my sleep. I went to investigate, only to find the rear compound gate open and dogs of all shapes and sizes surrounding a small, terrified dog.
She was tied to a post by a wire around her neck and the large male dogs were snapping at each other for an opportunity to mate with her. The Afghans had decided to have a go at breeding their own supply of fighting dogs.
Dave and I chased away the males and released the captive. I held on to the wire tied around her neck, not wanting her to run away, but I needn't have worried. She walked beside me as I went over to where Nowzad and RPG were both desperate to get out.
Meet the pack, continued: Jena, pictured with one of her pups
When I let them out of the run, she happily trotted in. 'Guess that's another one, then,' said Dave.
I called Lisa but before I could tell her anything she announced: 'I've found a rescue centre in northern Afghanistan.'
'How many dogs did they say they would take?' I asked.
'I told them you had two dogs that needed rescuing ... Oh no, you haven't?'
Our new arrival settled in well. Both Nowzad and RPG appeared to defer to her. The lads had already named her, but I wasn't too happy with their choice: Jena, after their favourite American porn star.
The problem was going to be getting the trio to the rescue shelter before the end of my posting in a few months.
The shelter was 700 miles from our base and I didn't have the contacts to broker a deal with a local driver to deliver them. I doubted anyone else would want to take the responsibility of looking after them when I left.
In fact, problems were mounting up. Rumours about the dogs filtered out of our camp and an officer pulled me over one day to remind me of the strict policy on animals.
'There will be no dogs adopted by anybody in this unit. And I shouldn't have to tell you that there will not be any use of military assets to transport the animals back to the UK or anywhere else for that matter.'
Before long, Jena started putting weight on - she was pregnant. Then another small funny-looking dog turned up in the compound. Her neck was nearly double the thickness it should have been for an animal this size. She had been bitten by a snake.
The doctor sorted her out and we christened her AK, after the Russian AK-47 automatic weapon. So now we were four.
Meanwhile, Nowzad was becoming unpredictable around everyone apart from me. One night, when he almost bit one of the lads, a switch inside me flipped.
The frustration of being target practice for the Taliban, the months of sleep deprivation, burst to the surface.
'Nowzad! That's it! No more,' I shouted as I dragged him towards the gate. 'Nobody will want you at the rescue, you're a total pain in the a***.'
I pushed him out. Later that night I heard his whimpering. I climbed up the ladder and looked over the 15ft wall.
There was Nowzad propped against the gate, looking rejected. He was waiting to come back to what he regarded as his home. I forced myself to ignore him.
An hour later I climbed the ladder again. I couldn't see him at first but then I caught sight of him, curled up. His coat was camouflaged with the glistening, white frost. I opened the gate.
Meet the pack, continued: Tali, pictured with the puppies she sneaked into the base
'It's me, come on, dog,' I whispered. He pushed clumsily to his feet. His stumpy tail wagged uncontrollably as I brushed the ice crystals from his coat. I rubbed his head.
'Sorry, let's not do that again, eh?' I danced around with him by the gate feeling just as happy to see him as I believe he was to see me.
Then, to crown it all, one day returning from patrol, Grant, my mortar man appeared and motioned for me to follow him.
He led me to the rear gate where a small crowd of lads had gathered and were watching a grubby, grey-brownish blob of fur being forced through a tiny depression in the mud under the bottom of the metal gate.
'I'll be damned!' I said. It was a tiny puppy, probably no more than a few days old, being forced through the gap.
The force pushing the puppy came into view. A dirty snout with a bright pink nose appeared first, followed by a thin, mud-streaked head. It was a scatty white dog I had seen running through the compound a few days ago.
Somehow she squeezed through the gap, then gave the puppy a quick sniff and a prod before picking it up between her teeth. We all watched as she padded over to a small mud cave.
'That's the third,' Grant said. The mother carefully placed the newborn puppy down alongside two other small, curled-up bodies before heading back to the gate.
'Looks like the word is out on the street, Sergeant,' Grant smiled. 'All strays welcome.'
Within minutes we saw another puppy emerging through the hole. Then there were two more.
'This is getting ridiculous,' I sighed. 'If I didn't know better, I'd say the dogs are talking to each other out there.'
The new dog, who we called Tali, short for Taliban, was barely settled in with her litter when Jena delivered eight puppies on New Year's Eve.
We now had five adult dogs, and 14 puppies. Our boss had turned a blind eye to our small dog welfare operation, but I couldn't count on the incoming officer to be as accommodating.
We needed to get the dogs to Kandahar, where the people from the rescue centre said they could collect them.
I had a brainwave. The ANP detachment we had bought Nowzad from had been replaced by a new bunch with whom we got on really well.
Through our interpreter, Harry, I asked the commander if he could find us a vehicle and driver to make the trip. After much discussion, Harry announced: 'The commander will make it happen.'
The plan was simple. For $400 the commander would hire a vehicle that would drive from Now Zad to Lashkar Gar; once there another vehicle would transport the dogs to Kandahar.
But the days ticked by and there was no news of the commander's vehicle. I received regular updates from one of the policemen, Rosi. I didn't have a clue what he was saying but the shame in his eyes was plain to see.
Finally, it was the day of our departure. Time had run out. The dogs would have to leave the compound when we did. We'd decided to leave the dogs with as many ration packs as we could spare in a deserted compound nearby.
Rosi would feed them for the remainder of his stay. When the time came for him to leave, he would leave the compound gate open. I knew it wouldn't be long before they starved.
I wondered whether I'd done the right thing for the dogs. I'd given them an unfounded trust in humans. That might not be the best thing for them once I'd left.
We were just about to move the dogs when one of the Afghan policemen started shouting excitedly. He was balanced on top of the wall, beaming and repeating just one word over and over: 'Taxi! Taxi!'
Our transport had finally arrived.
• One Dog At A Time, by Pen Farthing, will be published by Ebury Press on February 5. To order your copy at £12.99 with free p&p call the Review Bookshop on 0845 155 0713.
The pups of war, by the British soldier who saved them from horrors of the Afghan front | Mail Online