The Corruption Investigation Office for High-ranking Officials(CIO) began reviewing on whether to investigate allegations that Yoon Seok-youl incited the opposition to file complaints against pro-government figures while he was prosecutor-general.

An official from the agency said on Tuesday that it is too early to say whether an investigation will be launched or comment on its timing.

The official added that the CIO is looking into the prosecution's fact-finding study, new allegations from political parties and the media, and relevant legal issues.

On Monday, a civic group accused the leading opposition presidential contender of power abuse, obstruction of the exercise of rights, leaking official secrets, and violating the election law, the public officials law and the privacy law.

While Yoon, as a former high-ranking prosecutor, can be investigated by the CIO, the alleged law violations are beyond the agency's jurisdiction.

The CIO is also expected to face challenges in applying the power abuse charge as filing a complaint is not an exclusive authority held by prosecutors.