“Through three decades of war, waves of Afghans have fled their homes along the eastern border areas, many of them seeking shelter in the Pakistani tribal regions next door. Last summer another wave of refugees surged through the area. But in a reversal, it is Pakistanis, not Afghans, who are fleeing war at home.”
Source: In Shift, Pakistanis Fleeing War Flow Into Beleaguered Afghanistan – NYTimes.com