Key Points

The probe comes about eight months after troops were mobilised to allegedly block lawmakers from attempting to lift Yoon's brief imposition of martial law, with former Defence Minister Kim Yong-hyun standing trial over allegations he played a key role in conspiring to commit insurrection.

"(The ministry) will review the overall process that led to the martial law imposition to correct mistakes ... and take necessary measures based on the findings," the official told reporters, adding the move reflects Defence Minister Ahn Gyu-back's push to rebuild the military.

Ahn, who took office as the country's first civilian defense minister in 64 years, has vowed to restore the military into one that is trusted by the people while shoring up internal morale by recognising those with merits and punishing those who should be held accountable.

He has also called for the military to adhere to political neutrality while focusing on its duty of protecting the public.

About 20 officials, including those from the ministry's inspection bureau, will take part in the investigation that could take up to two months, the official said, without specifying units that will be probed.

In July, the defence ministry began a separate process to reward soldiers who rejected "unjust" orders during the martial law imposition, in a move seen as an effort to boost military morale.

The move, however, also raised questions over the appropriateness of its timing as a special counsel team is looking into allegations linked to the martial law imposition, Yonhap news agency reported.

On Monday, South Korean jailed former first lady Kim Keon Hee had appeared at a special counsel's office to undergo questioning for the second time, less than a week after her arrest over corruption allegations.

Kim was brought to special counsel Min Joong-ki's office in central Seoul in a prison van to attend the questioning.

- IANS