evidence: There is little else to do in the border town of Wadi Halfa, where a local support group says upwards of 20,000 displaced people live in limbo, unable to cross the northern frontier into Egypt and escape the five-month war between the Sudanese army and paramilitary Rapid Support Forces. [...] Aref al-Zubeir, an architect, has been in Wadi Halfa since the first month of fighting. [...] But in June, Cairo tightened its visa rules to include children, women and older men, which has slowed the flow of refugees across the border and kept many stuck in Wadi Halfa.