The Pakistan government on Thursday sent paramilitary troops to a district virtually taken over by the Taleban, a day after Washington said Islamabad had abdicated to the militants by agreeing to impose Islamic law in the region. Surging violence across Pakistan and the spread of Taleban influence in the country's NW region has revived concerns about the stability of the nuclear-armed state, crucial to US efforts to stabilize neighbouring Afghanistan. Officials say the forces will protect government buildings in Buner district, where insurgents have begun patrolling the streets and mounting checkpoints. As the troops moved into the region, insurgents launched an attack on their convoy. The Taleban are reported to have moved several hundred men into Buner from the Swat Valley. The government sent six platoons - up to 300 men - to deal with the insurgents. A police official said that the troops were attacked as they were leaving the village of Totalai in the south of Buner district. The convoy was heading for Dagar, the central town of the largely mountainous district. Springboard Critics say that the militants can now use Swat as a springboard to take over new areas of the country. US Secretary of State Hillary Clinton earlier said the insurgency posed a “mortal threat” to world security. Speaking to a Congress committee, Mrs Clinton said the Pakistani government was “basically abdicating to the Taleban and the extremists”. “Local police are helpless and seem to have lost control,” said resident Shams Buneri. “Taleban are moving freely everywhere in the town.” US President Barack Obama is to meet with Zardari and Afghan President Hamid Karzai in early May, with efforts to clear Taleban and Al-Qaeda fighters from Pakistan's lawless tribal areas along the Afghan border high on the agenda. The top US military commander, Admiral Mike Mullen, arrived in Islamabad for talks with Pakistani officials as concerns mounted over the government's ability to check the Taleban's advances toward the capital, officials said. “Pakistan – it's a country that has nuclear weapons. My long-term worry is that descent, should it continue, gives us the worst possible outcome there,” Mullen said. But Pakistani authorities have rejected suggestions that they need outside military help to combat the insurgent threat. aJamiat-e-ulema-e-Islam, the country's largest Islamic party, told parliament on Wednesday. Militants earlier on Thursday torched seven trucks carrying fuel to Western forces in Afghanistan on the outskirts of the main northwestern city of Peshawar, police added. Haqqani disagrees However, Pakistani Ambassador in United States Husain Haqqani said that there are not immediate threats from Taliban to takeover Islamabad and ruled out guesses of people that Taliban have possessed potential to capture Islamabad overnight. Haqqani claimed the situation is under control and is being monitored by the Pakistani military. “Pakistan is facing many challenges in terms of threats posed by Taliban but Government is cognizant with its responsibilities and geared up to take the Taliban bull by the horns” Ambassador maintained adding, “Swat peace accord was aimed at disarming Taliban.”