Seoul, June 14 (AHN) A joint team of police investigators and prosecutors will soon question election watchdog officials over shortages of ballot papers during the June 3 local elections in South Korea, legal sources said Sunday.

The expected move comes as the National Election Commission (NEC) has taken flak for the shortages that temporarily suspended voting at 26 polling stations, mostly in Seoul, during the elections earlier this month.

The team completed a search and seizure on NEC's servers on Saturday to secure internal messages and other records as part of a probe into the cause of the shortages, Yonhap News Agency reported.

The team plans to soon call in front-line NEC officials stationed in areas that experienced the shortages for questioning before summoning senior officials, including the NEC's former chief who resigned over the incident.

The investigation is focused on whether NEC officials exerted undue influence regarding the printing of the ballot papers and how they responded to the shortages.

Under the election law, civil servants are restricted from using their position to exert undue influence in an election.

The team raided seven locations, including the NEC's headquarters, on Thursday as part of the probe.

Meanwhile, protests demanding a re-run of the elections over the ballot shortages continued for the 10th day at a vote counting site in Seoul's southern district of Jamsil.

As of 10 am, about 600 people rallied around SK Olympic Handball Gymnasium, according to an unofficial police estimate, sharply down from some 19,000 people gathered Saturday night. The protests have tended to grow larger later in the day.

Officials are preparing for a long drawn-out standoff as a short-term dispersal appears unlikely as the protests have happened spontaneously without an organizer.

A police official told Yonhap News Agency that the protesters are likely to return home once progress is made in the investigation into the ballot shortages.

The protests, which have blocked entrances to the stadium, have prevented sports organizations based there from entering its offices. The sports groups will hold a press conference on Monday to urge protesters to let them inside the stadium.