Yoo Jae-eun, center, a legal affairs official at the defense ministry, appears at the Corruption Investigation Office for High-ranking Officials in Gwacheon, to face questioning, April 29. Yonhap

A ranking defense ministry official, named as a suspect in allegations of external pressure on the military investigation into last year's death of a young Marine, was questioned by the anti-corruption investigation office Monday for the second time in four days.

The Corruption Investigation Office for High-ranking Officials (CIO) was questioning Yoo Jae-eun, a legal affairs official at the defense ministry, as a power abuse suspect Monday morning after grilling her for about 14 hours Friday.

The probe was launched after the Marines' former top investigator, Col. Park Jung-hun, lodged a complaint against Yoo and another defense ministry official last year, accusing them of exerting undue influence on his handling of the inquiry involving a young Marine who died during a mission to search for civilian victims of heavy downpours last summer. Yoo is suspected of talking on the phone with a presidential secretary before interfering in Park's probe.

Yoo was asked many questions by reporters at the entrance of the CIO in Gwacheon, just south of Seoul, but did not say anything other than that she would faithfully answer questions.

After questioning Yoo, the CIO is expected to summon former Defense Minister Lee Jong-sup and others on similar charges. (Yonhap)