The discovery of a dozen suicide vests packed with explosives in Kabul was a matter of deep concern, a grim indication that the Taliban were intent on carrying out a massive attack. The added shockwaves came from the location: they were found in the country's Ministry of Defence, less than a mile from President Hamid Karzai's residence and the headquarters of Western forces.
Eighteen serving soldiers were arrested. They were planning, it is claimed, to blow up the building and everyone in it as well as buses full of government employees. Yesterday afternoon there were contradictory accounts of what had happened from different ministries, while commandos searched the premises after reports that two would-be bombers had escaped and were still hiding there.
The extraordinary events in the Afghan capital came 24 hours after two British servicemen were murdered by an Afghan soldier at Lashkar Gah, the British headquarters in Helmand, and an American soldier was shot dead by an Afghan policeman at a checkpoint in Paktika.So far this year, 16 Nato soldiers have been killed by their Afghan allies, second only to fatalities caused by improvised explosive devices (IEDs), the insurgents' weapon of choice.
According to Pentagon figures released last month, an estimated 80 Western service members have been killed by Afghans in uniform since 2007, with 75 per cent of the attacks in the past two years. The fear of an enemy within is particularly relevant at this time in the mission, with the West's exit strategy predicated on training Afghan forces to take over security and, after Nato ends is combat status, a small number carrying on acting as advisers.
With the West's rush for the exit from the war depending on building up the size of Afghan security forces, some Afghan officials say that corners were being cut when it came to security checks. "The foreigners just want the numbers keep going up so that they can say they have finished their job and it is time to go," said one official. "In such situations it is not surprising that some bad people are slipping through."
General John Allen, the American head of the International Security Assistance Force in Afghanistan (Isaf ) insisted that these types of attacks are to be expected in this type of war. "We experienced these in Iraq. We experienced them in Vietnam. On any occasion where you're dealing with an insurgency and where you're also growing an indigenous force... the enemy's going to do all that they can to disrupt both the counterinsurgency operations and the developing nation's security forces."
Gen Allen acknowledged, however, that precautionary measures have had to be taken. "We have taken steps necessary on our side to protect ourselves with respect to, in fact, sleeping arrangements, internal defences associated with those small bases in which we operate, the posture of our forces, to have someone always overwatching our forces. On the Afghan side, they are doing the same thing. They're helping the troops to understand how to recognise radicalisation or the emergence of extremism in individuals who may in fact be suspect."
One force which was seen as keeping the Islamists at bay – especially from Kabul and other major cities – and out of the armed forces, was the Afghan intelligence service, the National Directorate of Security. However, its head, Amrullah Saleh, resigned two years ago in protest at what he claimed was President Karzai surrounding himself with Islamists. His deputy, Abdullah Laghmani, had been assassinated by a Taliban suicide bomber a few months previously. With the two men gone, western officials began to notice a deterioration in the security situation.
Taliban attacks in Kabul have increased since. But although the preparations for the bombing inside the Defence Ministry were obviously part of an organised operation, there is little hard evidence of systematic large-scale infiltration.
Afghan observers hold that most of the recent attacks by Afghan security forces on their western colleagues have been sparked by anger at the burning of Korans by US officials at Bagram air base and the massacre of 17 villagers by US sergeant Robert Bales.
Interventions by President Karzai, such as describing the US and British troops as "devils" and the Koran burning – a crass mistake but not something done out of malice – as "an act which can never be forgiven" have also been inflammatory in the febrile atmosphere.
Following the killing of five soldiers from the Grenadier Guards Battle Group in Nad-e-Ali by an Afghan they were training, called Asadullah, stricter vetting procedures were brought in including more thorough background checks and biometric testing. However, in August 2010 three more soldiers, from the Royal Gurkha Rifles, were killed in Nahr-e-Seraj by an Afghan soldier, Talib Hussein.
Haji Wassim Nasruddin, who once fought alongside the insurgents in Pashmul, near Kandahar, but gave up arms under a reconciliation programme, and now lives in Kandahar City, said: "We never organised our young men to join the police and army.
"We hated the police in particular, because they were corrupt. But because they were corrupt, they sometimes helped us and because they were afraid, they sometimes helped us. And, of course, if any of them attacked foreigners ,we would give them shelter and call them true Muslims."
Wahid Muzhda, a former Taliban foreign ministry official and now an analyst of the insurgency, agreed. "All these killings are not linked to the Taliban. The recent Koran burnings and the shooting of children are affecting the minds of the Afghan soldiers. They think: if the foreigners are coming here to defend Afghanistan, why are they killing children?
"But it is effective, trust is being undermined between the international forces and the Afghans. How can foreign soldiers mentor if they are worried about the Afghans they are teaching? It is not possible."
Coroner praises bravery of bomb officer
A coroner commended the bravery of a bomb-disposal officer yesterday while ruling that she had been unlawfully killed during service in Afghanistan.
Captain Lisa Jade Head, of 11 Explosive Ordnance Disposal Regiment, the Royal Logistic Corps, lost her limbs in a blast in Helmand province on 18 April 2011. The 29-year-old, from Huddersfield, West Yorkshire, died the next day.
Colonel Gareth Collett, an army bomb-disposal expert, also praised the professionalism of Capt Head yesterday.