The massive blast that tour through a police bus in central Kabul this morning signaled a worrying development for the Afghan government and its western backers.

Not only was it the single biggest strike by Taleban insurgents since they were removed from power in 2001, with up to 35 people killed and 35 people injured, and not only was it in central Kabul, but it was the fifth suicide blast in three days indicating an upping in the tempo of attacks.

What is also worrying is the amount of damage caused by the bomber. Two years ago it was very rare if a suicide bomber killed more than one or two people.

At one stage more bombers had died in blasts than anyone else. This latest attack shows the Taleban have learnt lessons and are now able to carry out more effective strikes, with devastating results.

This has led many to speculate that insurgents in Afghanistan have been co-operating and learning from their Iraqi counterparts.

Last year Taleban rebels would show a suicidal zeal in pitched battles with Nato troops, they lost thousands of fighters but their impact was limited. The fear is that this year they will focus more energy on a suicide campaign in Afghanistan’s cities.

The psychological impact of an extended suicide campaign would seriously undermine the reconstruction efforts of the country.

At the scene of the latest attack several police officers complained that the job was now becoming too dangerous and the $50 American they were paid a month was not compensation enough. Others however insisted that it was their duty and they would never give up in the fight against the Taleban.

A crime scene investigator, picking through the bomb site, said he had never seen such a large blast. Aside from the police bus, the roof of which was ripped off, another bus and a mini bus were also damaged.

Bits of body were scattered in nearby trees, blood and flesh covered the charred remains of the bus and nearby walls.

The side of the mini bus was peppered with puncture holes from ball bearings that the bomber had packed into his explosives vest.

The blast was so large the noise could be heard across town, employees in nearby buildings said that the ground shook.

The attack happened in one of the most secure areas of Kabul. The bus with police recruits and teachers was parked up outside a police station and near to the Kabul governor’s house. A policeman at the scene said the location of attack was particularly poignant; “If they can attack us here, it is a big shame for us. What hope is there for the rest of the country?”

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