Afghanistan on Thursday began a massive audit of 8.1 million ballots cast in the run-off round of its controversial presidential vote, hours after a brazen Taliban raid on Kabul’s airport. The audit is aimed at reversing a destabilising political crisis that has threatened to widen the country’s ethnic fissures as foreign troops prepare to withdraw after more than a decade of war. Some 23,000 ballot boxes are being transported by the Afghan Army.