Prosecutors here said Friday they have requested an arrest warrant for an Ulsan vice mayor suspected of illegally intervening in the 2018 mayoral election in the southeastern metropolitan city.

The Seoul Central District Prosecutors Office said it asked the court Thursday evening to issue a pre-trial warrant to detain Song Byung-gi, Ulsan's vice mayor for economic affairs, on charges of conspiring with several presidential aides to influence the city's mayoral poll last year in violation of the Public Official Election Act.

The warrant request came about one month after Seoul prosecutors took over the case from their counterparts in Ulsan and found Song was the source who tipped off a former presidential office Cheong Wa Dae official to bribery allegations involving former Ulsan Mayor Kim Gi-hyeon's confidants.

Kim, who was then seeking reelection as mayor in the June 2018 elections as a candidate of the main opposition Liberty Korea Party, lost the race to current mayor Song Cheol-ho of the ruling Democratic Party, a longtime friend of President Moon Jae-in.

The case blew up into a massive investigation after Kim publicly claimed that the Ulsan Metropolitan Police Agency deliberately raided his office a few months ahead of the election with the presidential office behind the move.

Kim and his confidants were acquitted by a local court after the election ended, while Cheong Wa Dae has flatly denied all allegations of election meddling.

Song Byung-gi is accused of discussing campaign strategies and pledges in favor of Song Cheol-ho in meetings with Cheong Wa Dae and police officials.

Prosecutors reportedly stated allegations of election meddling by presidential aides and police officials in the arrest warrant request, regarding them as accomplices in the vice mayor's suspected illegalities. The Public Official Election Act strictly prohibits civil servants from acts influencing elections in order to ensure their political neutrality.

Prosecutors also suspect that Cheong Wa Dae extended support to the construction of a public hospital in Ulsan, a major industrial city about 415 kilometers southeast of Seoul, in accordance with campaign pledges by Song Cheol-ho. They have reportedly secured clues from memos of Song Byung-gi that indicate he held several discussions with Cheong Wa Dae officials in Seoul regarding Song Cheol-ho's campaign pledges beginning in the fall of 2017.

The latest development was disclosed after a Seoul court rejected an arrest warrant for former Justice Minister Cho Kuk earlier in the day in a probe into his suspected role in ending an inspection into bribery allegations involving a former Busan vice mayor.

Earlier this week, prosecutors filed for an arrest warrant for Cho, former senior presidential secretary for civil affairs, on charges of abuse of authority in connection with the bribery case of the now-arrested Yoo Jae-soo. (Yonhap)