A South Korean officer directs vehicles heading towards the inter-Korean industrial complex in Kaesong in North Korea,as South Korean Army soldiers walk past the Customs,Immigration and Quarantine office,just south of the demilitarised zone separating the two Koreas,in Paju,45 km from Seoul. North Korea reopened its border with the South,ending a self-imposed nine-month blockade on a vital source of cash for its leaders as their ravaged economy is squeezed by tightening UN sanctions.