Pakistan says it has started building a fence along the Afghan border in areas where it says militants have launched cross-border attacks on security posts in recent weeks. <br/><br/>Gen. Qamar Javed Bajwa, the head of Pakistan's armed forces, announced the construction of fencing in "high threat zones" yesterday during a visit to tribal regions along the border, saying it was in the interest of both countries.'<br/>'<br/>The two countries share a 2,400-kilometer border known as the Durand Line, which was drawn during colonial times and is not recognized by the Afghan government.<br/><br/>Building a fence along the disputed border could further heighten tensions between the two countries, which have long accused each other of turning a blind eye to Islamic militants operating along the porous frontier.