Kim Jin-wook, the head of a new powerful state investigative agency, said Friday the agency will not take on a travel ban case involving a former vice justice minister as its first case, citing "realistic conditions."

"After serious consideration, we have decided to refer the case back to the prosecution," he wrote on the official Facebook page of the Corruption Investigation Office for High-ranking Officials (CIO), ending days of speculation that the case could be the agency's highly anticipated first task.

The case in question centers on the accusations against the Ministry of Justice and prosecutors that they either overlooked or participated in the alleged illegal process of imposing an exit ban on Kim Hak-ui, who briefly held the vice justice minister post in 2013.

In March 2019, Kim was stopped at Incheon International Airport, west of Seoul, from leaving the country, as prosecutors sought to reinvestigate allegations that he received sexual favors from a local constructor more than a decade ago.

According to complaints made on the case, the departure ban did not follow due procedures and justice ministry officials illegally checked Kim's personal information 117 times in March 2019.

Although the case falls into the CIO's investigation scope, the CIO chief said the agency was not ready to start full operation, with its hiring process still going on.

"We could not ignore the realistic conditions that made us unable to be fully devoted to investigations at this stage, because we still need 3-4 weeks to hire prosecutors and investigators," he wrote.

Last Wednesday, the Suwon District Prosecutors Office transferred the case, in which two high-ranking incumbent prosecutors are suspected of exerting undue influence, to the CIO. It was in accordance with the relevant law that allows the CIO to supersede other investigative agencies and to have the power to require them to transfer a case involving high-ranking officials.

The CIO, which began operation in January, is authorized to investigate and prosecute corrupt former and current public officials, including the president, lawmakers and prosecutors. (Yonhap)