The British sniper lay on the rooftop of a compound within sight and range of about 20 Taleban armed with Kalashnikovs and rocket-propelled grenades in a dugout, and waited for the order to “go lethal”. He had already fired warning shots but the rounds from his long-range 338 rifle had failed to scare them from their bunker.

Overhead, a lone Desert Hawk unmanned aerial vehicle (UAV), not much more than a polystyrene model plane but with a fancy camera on board sending pictures back to the commander, detected that the Taleban were preparing for a fight.

They had the advantage of being in a well-defended position, and the British troops of D Company 2nd Battalion The Parachute Regiment had to cross open ground to get within shooting range of their bunker.

The sniper received his order and three minutes later he got his man. “One down, one down!” – a corporal shouted. Another mortar blast with a smoke round burst near the enemy bunker. It was launched to confuse the Taleban, encouraging them to believe that a full-scale British attack was about to take place. However, the aim of the operation was not to “go kinetic” and flush out the enemy from their southern frontline position across the fertile valley from the isolated British camp at Kajaki, but to familiarise the newly arrived Paras with the terrain near their mountain base and to upset the Taleban early on a Sunday morning.

During any encounter with the Taleban it is wise to be prepared for a gunfight, and the company of para-troopers who left at 6.30am were ready for anything.

The patrol’s tactical air controller, the role played by Prince Harry in Afghanistan recently, can call in air support if needed. The target area was a group of trees about two miles from the British base in the north of Helmand province, behind which the Taleban had dug a series of bunkers.

The military operation in Afghanistan may be all about winning hearts and minds but here in Kajaki, which Major Mike Shervington, the officer commanding D Company 2 Para, likes to call the northernmost tip of the British Empire, the threat is real.

The Taleban are not interested in hearts and minds.

To reach the target, 10 Platoon and 11 Platoon of D Company split up, one going along a dirt road known to the soldiers as Highway 611 and the other squelching through the irrigation ditches of Tally Alley, renamed Reg (for Regiment) Alley by 2 Para, which winds through the poppy fields in the green zone by the River Helmand.

The countryside is pure Monet, with splashes of pink, purple and red as you walk along the rows and rows of poppies ready for harvesting for the opium warlords.

The soldiers of 10 Platoon report being waist-high in water in the irrigation ditches. Suddenly, we can see the muzzle flashes from the target’s rifles. But we are at the limit of the Taleban’s range.

The Paras of 11 Platoon continue walking along Highway 611 carrying their heavy gear, the thick-walled compounds on the right screening them from the Taleban position.

To the left is where two Marines from 40 Commando were killed three weeks ago by a pressure-pad improvised explosive device. Every soldier on this foot patrol is watching out for the buried devices.

The night before, Paras at an observation post with thermal imaging equipment spotted several Taleban digging furiously outside a compound, clearly laying an explosive device.

They received a few warning shots from a 50 calibre machinegun and then a lethal round, which sent them scattering back to their base.

Before any action can be taken, the Taleban must be positively identified. “We can’t just call in air to bomb the Taleban. We have to be careful to avoid any possibility of collateral damage – civilian casualties,” Captain Joe Walker, 29, says. The sniper was given his order to “go lethal” because there was no doubt who was in the bunker 800 metres away. All the local poppy farmers had withdrawn to safety.

“Taleban man will probably just have his AK [Kalashnikov], a magazine [of ammunition], bottles of water and a pair of flip-flops, and look at all of us,” 36-year-old Major Shervington says. He calls off the sniper when the Para sees through his sights that a child has appeared near the target.

The patrol from D Company is accompanied by three dogs, Harvey, an explosives search springer spaniel, handled by Lance Corporal David Baron, 25, and two mongrels adopted by the troops, called AK and Charlie.

They are unfazed by the shooting and do not react when the Paras blast holes through a compound wall, using a bar mine. After five hours, the patrol heads back to the base.

The soldiers are itching to get to the Taleban, but Major Shervington is more patient. “This is one of our first patrols in Kajaki, we need to get to know the terrain, and we’re here for six months,” he said.

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