The Pakistani army is locked in a fierce battle to stop fuel and arms supply routes to British and American forces in Afghanistan falling under Taliban control.

Last week Pakistani troops launched a series of raids on villages around Peshawar, capital of the North West Frontier Province, in pursuit of a Taliban commander blamed for bomb attacks that have destroyed more than 40 fuel tankers supplying Nato troops in Afghanistan.

They claim that Mohammad Tariq Alfridi, the commander, has seized terrain around the mile-long Kohat tunnel, south of Peshawar, three times since January. He has coordinated suicide bomb attacks and rocket strikes against convoys emerging from it.

The Taliban attacks stretch all the way south from the Afghan border to Karachi, where weapons, ammunition, food and oil supplies arrive at the docks before being transported by road.

Last week western diplomats in Karachi said there had been an alarming increase in Taliban activity in the city. Local politicians said they had been warned by intelligence officials that 60 Taliban families had fled to Karachi from tribal areas close to the Afghan border and had begun to impose strict Islamic law. They had recently posted notices throughout the city forbidding girls from going to school.

The army’s antiTaliban offensive in the tribal areas appears to be hitting the militants hard. Last week Maulvi Omar, a Taliban spokesman, said that his fighters would lay down their arms if the army ceased fire. His offer was ignored.

The battle for the tunnel began at the start of the year when Taliban fighters seized five trucks carrying weapons and ammunition. They held the tunnel for a week before they were driven out in fierce fighting. Since then Tariq and his men have returned several times to attack convoys. The army launched its latest onslaught after a suicide bomb attack at one of its bases near the tunnel six weeks ago. Five people were killed and 45 were injured, including 35 soldiers, when a pickup truck packed with explosives was driven into a checkpoint.

When The Sunday Times visited the approaches to the tunnel last week, several bridges along the road bore the signs of explosive damage and bullet holes. Villagers said the Taliban had not fled but had melted into the background to wait out the army assault.

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