Prosecutors conducted a search of the Presidential Committee for Balanced National Development as part of an ongoing probe into allegations that the presidential office interfered in the mayoral election in Ulsan. 

Officials searched the committee's office located on the fourth floor of the government complex in Seoul on Thursday and secured records related to its advisory activities at the time of the provincial elections in June 2018.

The committee is a presidential advisory organ established to seek balanced national development and ease regional unbalanced growth.

The raid was designed at looking into the process of how Ulsan Mayor Song Cheol-ho formulated and implemented his campaign pledges. 

Mayor Song was appointed as an adviser to the committee in late 2017 when he was preparing to run for mayor. 

Prosecutors are believed to be looking for clues regarding the possibility that he received help in drafting his campaign pledges from the committee's advisory board which included ruling party officials.