The border town of Spin Boldak is a dangerous place. Men in black turbans zip around on motorbikes, smugglers rub shoulders with the Taleban, the border police are corrupt and weapons and drugs are everywhere.

The town is dusty, smoky and rugged, like a Wild West frontier town. The difference is that there is no alcohol and fortunes are made smuggling heroin, not prospecting for gold.

“Just nine miles (15km) over there is a Taleban training camp,” Muhammad Nasim, 27, the head of the Afghan border police, told The Times pointing into Pakistan to a cluster of mud buildings.

“The Taleban have no problem crossing the border . . . they are trained by Pakistan.” The ease with which Taleban fighters can pass through an official border crossing is certain to concern British troops in Helmand province, which borders Kandahar.

Intelligence reports suggest that Taleban fighters are massing in Quetta, across the border, for a spring offensive and it is feared that Britain’s 5,000 troops in Helmand will bear the brunt of it.

Pakistan has given repeated assurances that it is clamping down on Taleban insurgents after accusations by Afghan and Western officials that they get training, finance and a safe haven in the neighbouring province of Balochistan. President Musharraf of Pakistan has said he will mine and fence known insurgent crossings.

The picture on the ground is very different: here at the main border crossing guards were seen taking bribes in a way that would allow smugglers, Taleban fighters or even suicide bombers through checkpoints unchallenged.

“It’s all bulls**t that Musharraf is trying to stop them. He supports the Taleban. They [the Pakistanis] give them weapons and training,” said Khaliq Daad, 32, a fierce-looking, one-eyed smuggler who lives in Chaman on the Pakistani side of the border.

“We have to pay bribes every day to the Pakistanis so that they don’t search our vehicles,” said Zadar Muhammad, 30, another smuggler from the town of Chaman.

For less than the equivalent of £1, a man with no passport can pass through Pakistani and Afghan checkpoints without so much as a frisking; for £25 a driver can get his truck through without documents.

The road is paved from Spin Boldak to Quetta, capital of Balochistan, and about 50,000 people cross the border every day. It is believed that among the masses are Taleban fighters and suicide bombers who use Quetta as a training ground and a place to rest during the winter months.

When The Times visited the border post, Pakistani guards could clearly be seen taking bribes and allowing people through without searching them. It is not just Pakistanis who take bribes, however.

“Both sides are asking for bribes,” Akhtar Muhammad, 28, the second-in-command of the Afghan police force in Spin Boldak, told The Times with alarming honestly.

What makes the border so tricky to police is that many of the local tribes don’t recognise it as a border at all. The Durand Line between Pakistan and Afghanistan was drawn up by the British in 1893 to split up the fierce Pashtun tribesmen who inhabit these parts. The border split families up and tribesman still cross the border for tea with a relative.

“The world should realise we don’t recognise this as a border. It’s difficult to tolerate as we are one people and one nation,” Akhtar Muhammad said.

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