The Corruption Investigation Office for High-ranking Officials(CIO) raided the defense ministry on Friday in their investigation of alleged power abuse by the former defense minister Song Young-moo. 

The CIO carried out a search seizure of the ministry headquarters, as well as the residences and offices of the ex-minister and other officials, including one of his former aides and a former ministry spokesperson.

Song, a defense chief during the previous Moon Jae-in administration, is accused of forcing senior ministry officials in July 2018 to draw up and endorse documents that refuted a media report, which said that he denied any legal problems with a controversial contingency martial law plan under the former Park Geun-hye government. 

The martial law plan was prepared by the now-defunct Defense Security Command when former President Park faced impeachment in 2017.

The prosecution has also launched an investigation into the same allegation after the ruling People Power Party(PPP) filed a complaint last September.

Based on the gathered evidence, investigators are expected to summon Song and others for questioning.