Pakistan must attack insurgents in its northern areas and tackle extremists threatening its stability and complicating international efforts in Afghanistan, a senior US diplomat said Thursday. The United States is committed to helping Pakistan fight insurgents, deputy assistant secretary for South and Central Asian Affairs Patrick Moon told reporters in Kabul. Hours earlier suspected US spy drones fired missiles into a school set up by a Taliban commander in tribal area, killing 11 people, in the latest in a string of attacks that have raised tensions between the countries.