How the British hostages were rescued in Afghanistan Meanwhile the special forces began to plan for the worse case scenario and over the following 24 hours, started to reconnoitre a series of potential helicopter landing sites - not an easy task given the nature of the terrain, highly mountainous and thick with forest. The local population was composed of mainly farmers and shepherd and insurgent activity in the area was limited but there was a large criminal element in the region, which sits on one of the main opium smuggling routes into Tajikistan and onwards into Russia, the troops were told. Timing, as in all special forces operations, was critical. Launch a rescue mission too early, and the hostages risked being executed leave it too late and there was every chance the women could disappear only to resurface weeks later facing execution on an al-Qaeda video. While the British and US forces planned and rehearsed their rescue mission, back in London the Prime Minister chaired several Cobra (Cabinet office Briefing Room A) meetings where he kept senior members of the cabinet informed of the latest events. In attendance amongst others were the heads of MI5 and MI6, the Director of Special Forces, General Sir David Richards, the Chief of the Defence Staff, Tim Allen, Sir Kim Darroch, the National Security Advisor and the Philip Hammond, Defence Secretary. "I have given my approval to COMISAF [General John Allen, Commander of the International Security and Assistance Force] for a rescue mission to be launched," he told the meeting gathered round a large conference table in the windowless room under Downing Street. It is just a matter of when and how. Then, early on Wednesday, the Predator gleaned some vital intelligence. Miss Johnston, 28 and 26-year-old Moragwa Oirere also an aid worker were separated from their two Afghan colleagues and being held in a different cave. Of more concern, however, were the details of an intercepted phone call in which the Taliban had begun to urge the kidnappers to "make a declaration of intent." Back in Kabul intelligence officers assumed this meant that at least one of the hostages risked being murdered. The development was what the American special forces called a "game changer." The time for "executive action" had arrived. By mid-afternoon on Friday, during the twelfth consecutive Cobra meeting chaired by David Cameron, those present were informed of the latest developments, including the imminent launch of a hostage rescue operation - no further information was given. Back in Kabul, the decision was taken to split the hostage rescue force. A 28-strong SAS detachment would be responsible for freeing Miss Johnston and her Kenyan colleague, while the US team, composed of members of Seal Team 6 - the same unit who shot dead Osama Bin Laden - were tasked with rescuing the Afghan hostages. Everyone was fully aware of how these things can go tragically wrong as we saw when Linda Norgrove [the British doctor] was killed in a botched hostage rescue operation 18 months ago. So there was a real feeling that we had to get this one right," said one source. The intelligence from the aerial reconnaissance was at best sketchy but it was thought that at least four kidnappers were guarding Miss Johnston and Miss Oirere, while a further seven were holding the two Afghan women. Both groups were armed with the ubiquitous but deadly AK47 assault rifle, rocket propelled grenades and a PKM, a Russian belt-fed machine-gun, which is capable of shooting down a helicopter. Late on Friday morning, the British and US rescue teams were told that the operation had been confirmed. The mission was straight forward: Rescue the hostages, kill the kidnappers. H-hour, the launch time for the operation was 5pm local time. The rescue force flew to a rendezvous on the edge of the Koh-e-Laram Forest in MH-60L Blackhawk helicopters flown by pilots from 160th Special Operations Aviation Regiment (Airborne), nicknamed the Night Stalkers. Each helicopter is equipped with a M230 Chain Gun and rockets pods. Riding "shotgun" were two US Apache helicopters to provide "flank support" for the operation. The SAS troops went in relatively light order - dressed in black with machine guns, pistols, knives and both stun and hand grenades. Each man was equipped with night vision goggles and a helmet-mounted camera. A medical team was also attached to each of the assault ready to give immediate first aid to the hostages. The first troops on the ground secured a helicopter landing site (HLS) at the top of a rocky valley and coordinated the arrival of all of the Blackhawks until the full compliment of troops had arrived. The HLS was located around two miles away from the kidnappers" camp - but the sound of any approaching helicopters would have been muffled by the thick forest, or so the special forces hoped. In the early evening light, the US and British special forces were closing in on the caves where the hostages were being held. Back at ISAF Headquarters in Kabul, General Allen and his British deputy, Lieutenant General Adrian Bradshaw, watched the operation unfold on a bank of television screens inside the main operations room in so that they could maintain "full situational awareness." Just as the sun was beginning to set the British troops approached the cave where they believed Miss Johnston and Miss Oirere were being held. The SAS held their ground until their US colleagues reached their assault positions. It was vital for both attacks to be executed concurrently. Weapons and radios were given a final check and night vision goggles activated. Minutes later the special forces teams rescuers were given the order to assault. The soldiers moved into the darkness shooting dead the kidnappers with silenced weapons. Several were dispatched with a "double tap" the preferred method of killing - two bullets in the centre of the forehead. The US special forces cleared and secured their target, killing seven kidnappers in the process but no hostages had been found. For an instant commanders faced the dreadful possibility that the four aid workers had been moved. Seconds later, however, the tension was broken when the SAS team commander's radio crackled into life, reporting that all four hostage were alive and well, before adding that a further four kidnappers had been killed. The dead were searched for intelligence and weapons while medics checked the four women to ensure that none had been injured during the brief firefight. Within minutes the helicopters were brought forward to a clearing near the edge of the forest where the four exhausted but relieved hostages were flown back to ISAF headquarters in Kabul. At 2am British time Downing Street was informed that the rescue operation had been a complete success. The Prime Minister was woken at 2.15am and was given the news. He stayed up until every member of the SAS was safely back in Kabul and spoke to several of the soldiers by phone praising their courage and thanking them for achieving a successful outcome. Miss Johnston was later taken to the British Embassy where she too received a call from Mr Cameron who also praised her courage for remaining calm throughout the entire ordeal.