The Taleban insurgency has fused with narcotic mafias in British-controlled Helmand province, sparking a Colombian-style drug war, officials in Kabul said yesterday.

Faced by the growing menace British Forces brushed aside longstanding unease over direct involvement in counter-narcotics this week, mounting their first big operation explicitly targeting drugs labs in the province.

Operation Diesel, which involved 800 British commandos and Special Forces, secured drugs from what officials said were processing labs linked to the Taleban. The drugs were worth $6million (£4million) at their source and much more on the streets of America and Europe. US officials estimate that the Afghan insurgents are now making up to $100million a year from drugs trafficking.

An Afghan government official involved in counter-narcotics told The Times: “Helmand is now just a criminal province, it is a Colombia situation. It is producing 60 to 70 per cent of Afghan opium. There are major international criminal groups processing and trafficking there.”

Officials were surprised by the violent backlash that met an attempted drug eradication campaign launched two weeks ago in what was previously one of the few openly pro-government areas of Helmand.

On two occasions the Afghan police and army force sent into Nawa and Nad Ali districts had to call for “in extremis” support from Nato jets, the first time Nato aircraft have dropped munitions to support what is theoretically a criminal rather than a military operation in the country.

The fierce resistance encountered by the troops has left officials wondering whether the violence is primarily Taleban-inspired or if a majority of local farmers are also now fighting the eradication forces. “The traffickers and the Taleban want a destabilised Government,” the Afghan official involved with counter-narcotics said. “They are going to have to be taken on. Nato forces must start doing that. We've seen General Craddock saying that and being criticised. This is the first major Nato-led operation, some nations are going to be against that, but they are living in yesteryear.”

The commander of Nato forces in Europe, General Craddock, said that the Taleban were making $100million a year from drugs trafficking and told the Munich Security Conference on February 9 that Nato operations against major drug lords would begin “within days”. It follows serious internal rifts within Nato, including reported opposition from Italy, Spain and Germany, to the use of Nato forces against narco-criminals. A Nato spokesman insisted that such operations could only take place where there was evidence linking the narco-traffickers to the insurgents.

“We want to show that eradication will not go away,” one Western diplomat said. “We must make sure that what we are doing doesn't have a detrimental effect. We do not want a situation where we end up with more instability than we started with. We want eradication to help the governor to build a stable province.”

Local people in Nad Ali said that Taleban militants were setting themselves up as defenders of the local populace, exploiting anger after Nad Ali and Nawa districts were the only areas of Helmand to suffer poppy eradication during the past three years. This was largely because their pro-Government standing made them one of the few areas Government eradication teams could enter.

“The people have joined with the Taleban,” said Abdul Ahad Helmandwal, the head of the Nad Ali district council of elders. “They are supporting the Taleban because the Taleban have promised to defend the poppy. I am saying this only because the Government has for the past three years eradicated Nad Ali and Nawa and not the other areas of the province.”

Other local people, speaking by telephone from Nad Ali, said that the Taleban forbade them to grow wheat that was to be distributed by the British Government in November under an “alternative livelihood” scheme. A Taleban commander from Nawa admitted that the insurgents' increasing access to smuggling profits and tax receipts from poppy cultivation was undermining their ideological foundations and turning the Islamist militancy into a criminal enterprise.

“Before, the Quetta Shura [the Taleban's high command based in Pakistan] gave money to the big leaders in Helmand not to the small commanders. Now the small commanders get money from poppy, from road blocks and from stealing,” said the man, an older commander who asked not to be named. “Everyone is working for themselves. This fight is not for Islam it is all for money,” he said.

The rise of a drug-dependent insurgency in Helmand where the Taleban are active contrasts with the rest of Afghanistan. Opium production is expected to decline 40 per cent this year, with as many as 22 of 34 provinces likely to be drug free. Western officials attribute the progress to a switch to legal crops caused by rises in wheat prices and a slump in the opium price due to overproduction in Afghanistan.

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