Huh Chul-hoon, secretary-general of the National Election Commission, apologizes to the public Tuesday at the commission’s headquarters in Gwacheon, Gyeonggi Province, over ballot paper shortages at some polling stations, including in Songpa district, Seoul. Photo by Asia Today

June 4 (Asia Today) -- South Korea's National Election Commission has failed to clearly explain an unprecedented ballot paper shortage in the June 3 local elections, leaving two Seoul ballot boxes uncounted and delaying the formal confirmation of the Seoul mayoral winner.

The commission said Thursday it would establish a fact-finding committee to investigate the ballot paper shortage that occurred during voting. The committee will be composed mainly of outside experts and will examine the cause of the problem, identify responsibility and recommend measures to prevent a recurrence, the commission said.

The controversy has continued because the commission has not provided a detailed explanation of how the shortage occurred or how many voters were affected.

More than a day after voting ended, the Seoul mayoral race had still not been formally completed. People Power Party candidate Oh Se-hoon's victory was effectively confirmed around 9:30 a.m. Thursday, but the vote count remained stalled at 99% for hours because two ballot boxes from Jamsil 7-dong's second polling station in Songpa district had not been moved to the counting center amid protests by residents.