The audit of all ballots cast in Afghanistan's June 14 presidential runoff was expected to begin Thursday, in hope of dissolving the deadlock over who won.
After transport to Kabul, the eight million ballots cast in the runoff are expected to be scrutinized for adherence to official standards, to prove or rule out ballot-stuffing and other irregularities. The process is expected to take several weeks.
The international peacekeeping force ISAF will supervise the ballots' transport from provincial offices to the capital, while candidates' representatives, the media, and domestic and foreign observers will monitor the audit.
Rival presidential candidates Abdullah Abdullah and Ashraf Ghani agreed to a full U.N.-supervised audit of the runoff poll and committed to abide by the results.
The audit was part of a deal mediated by U.S. Secretary of State John Kerry on Saturday, to resolve a dispute over who won the runoff election June 14, after an initial vote April 5.
Meanwhile Thursday, a four-hour attack by Taliban insurgents on Kabul international airport ended with the deaths of all insurgents involved.
Afghan security officials say they are in control of the facility. Police say the airport is undamaged. Planes were diverted to other airports.
NATO has a major operational base at the airport for the International Security Assistance Force fighting militants in Afghanistan.
This is the second major incident of violence reported this week in Afghanistan. On Tuesday, a car bomb detonated in a busy marketplace in the eastern province of Paktika, killing 43 people.