Lee launched an investigation on the senior presidential secretary for civil affairs last month as a series of suspicions arose over his alleged tax evasion and other irregularities.

Under the Independent Inspector General Act, the investigator can bring the case to the prosecution if there is any plausible ground to believe that a person subject to inspection has committed criminal acts.

Lee, meanwhile, is also at the center of a controversy, as local broadcaster MBC reported that he leaked information about his probe into Woo to a reporter, whose identity was withheld, through social media. Lee has been denying the allegations. 

By law, a special inspector can face a prison sentence of up to five years for leaking information related to ongoing work. (Yonhap)