By Terry Friel KABUL, Nov 9 (Reuters) - Taliban insurgents have fought back against Afghan government and Western forces with surprising intensity this year, strengthened by drug money and the ability to shelter in Pakistan, a top U.S. official said on Thursday. Assistant Secretary of State for Central and South Asian Affairs Richard Boucher said efforts to extend the rule of President Hamid Karzai's government deeper into the provinces had run into tougher-than-expected resistance. "As this extension of government goes out, we are challenging those people and they are challenging us back," he told reporters at the heavily fortified U.S. embassy in Kabul. "I think we have all been surprised by the intensity of the violence this year. It has a number of factors: part of it is drug money linking up with the insurgency. Part of it these people have the ability to operate in and out of Pakistan. "But we need to deal with it." More than 3,100 people, about a third of them civilians, have died this year, the bloodiest since U.S.-led forces ousted the Taliban's strict Islamist government in 2001. PAKISTAN ACCUSED OF BACKING TALIBAN Some senior Afghan officials accuse Pakistan of continuing to back its former protege with money, training and other assistance, a charge Islamabad denies. Afghan intelligence officials say they have presented solid evidence to the United States. However Washington says there is no official Pakistani support for the Taliban, but that more needs to be done to stop the group and other militants and criminal gangs moving freely across the rugged border. Boucher said Pakistan was using military, economic and other measures to prevent the Taliban using its territory as "a place of refuge or of support". In September, the Pakistani government and pro-Taliban militants signed a truce in the lawless Waziristan tribal area to end fighting between rebels and government forces and attacks into Afghanistan. But NATO and U.S. officials say cross-border attacks have jumped dramatically since the deal. Boucher's visit came as NATO forces killed up to 22 Taliban in an air strike in Kandahar province, the Taliban's birthplace and a rugged desert province bordering Pakistan's strife-torn Baluchistan region. The clash happened on Wednesday in an area near the provincial capital that was the scene of a major two-week NATO offensive in September that killed hundreds of Taliban. District police chief Ghulam Rasool said at least six more guerrillas were killed in another battle in the area on Thursday. The NATO-led International Security Assistance Force completed its takeover of security nationwide from a U.S.-led coalition in October. As part of that, it has pushed more troops into the volatile south. NATO and U.S. commanders say this has led to an upsurge in fighting this year. But many analysts say the Taliban's resurgence has been fuelled by record opium crops and growing frustration and anger at a lack of reconstruction, development and jobs.
