KABUL (Agencies) - Drawing strength from the chaos in neighbouring Pakistan, Afghan insurgents are using their growing control of the border area to plot increasingly brazen attacks against international forces, the NATO commander in Afghanistan said. US Gen David D McKiernan, who took over the Nato command in Afghanistan in June, said attacks have spiked this year. McKiernan said the insurgency is drawing its strength from a "deterioration of conditions across the border in Pakistan." "Militant sanctuaries are expanding in the tribal areas," The Washington Times reported on Wednesday, quoting McKiernan as saying in an interview with an American news agency. He said insurgents are mustering larger forces against international troops and carrying out more roadside bombings, suicide attacks and ambushes. McKiernan, who described the insurgency as "resilient", said the most violent attacks come near the Pakistani border and are often connected to Afghanistan's ring road that links the country's major cities. The four-star US general, who commands the 53,000-strong International Security Assistance Force, said soldiers are operating in a complex environment battling a resilient insurgency. McKiernan said the insurgency has benefited from Pakistani sanctuaries and a deepening sense of insecurity in Afghanistan caused by criminal gangs, drug traffickers, and smugglers often accused of links with government officials. And in a July attack that left nine American troops dead, upwards of 200 insurgents ambushed US soldiers in a mountainous region that borders two Pakistani districts so troublesome that Pakistan was forced to send in troops this month despite the government's attempts at a truce. Over the past several months McKiernan said Nato has seen an influx of Chechens, Turks and Middle Eastern fighters as well as "sometimes Europeans." Some are coming through Iran and others are getting off international flights at Karachi before heading northwest to training camps in the border regions. Worrying to McKiernan is the increased ease with which insurgents operate in the border areas and their unhindered forays into Afghanistan.