South Korean prosecutors detain ex-defense chief over martial law imposition, reports say

South Korean prosecutors on Sunday detained a former defense minister who allegedly recommended last week’s brief but stunning martial law imposition to President Yoon Suk Yeol, making him the first figure detained over the case, news reports said.

The reported development came a day after Yoon avoided an opposition-led bid to impeach him in parliament, with most ruling party lawmakers boycotting a floor vote to prevent the two-thirds majority needed to suspend his presidential powers. The main opposition Democratic Party said it will prepare a new impeachment motion against Yoon.

On Sunday, ex-Defense Minister Kim Yong Hyun voluntarily appeared at a Seoul prosecutors’ office, where he had his mobile phone confiscated and was detained, Yonhap news agency reported.

Other South Korean media carried similar reports, saying Kim was moved to a Seoul detention center. The reports said police were searching Kim's former office and residence on Sunday.

Repeated calls to the Seoul Central District Prosecutors’ Office, the Seoul High Prosecutors' Office and the National Police Agency were unanswered. An official at the detention facility in eastern Seoul hung up the phone when The Associated Press called.

Senior prosecutor Park Se-hyun said in a televised statement Sunday that authorities launched a 62-member special investigation team on the marital law case. Park, who will head the team, said the probe would “leave no suspicions.”

Yoon accepted Kim’s resignation offer on Thursday after opposition parties submitted a separate impeachment motion against him.

Kim is a central figure in Yoon’s martial law enforcement, which led to special forces troops encircling the National Assembly building and army helicopters hovering over it. The military withdrew after the parliament unanimously voted to overturn Yoon’s decree, forcing his Cabinet to lift it before daybreak Wednesday.

In Kim’s impeachment motion document, the Democratic Party and other opposition parties accused him of proposing martial law to Yoon. Vice Defense Minister Kim Seon Ho told parliament that Kim Yong Hyun ordered the deployment of troops to the National Assembly.

The Democratic Party called Yoon’s martial law imposition “unconstitutional, illegal rebellion or a coup.” It has filed complaints with police against at least nine people, including Yoon and Kim, over the alleged rebellion.

In a statement Wednesday, Kim said that “all troops who performed duties related to martial law were acting on my instructions, and all responsibility lies with me.”

Prosecutor General Shim Woo Jung told reporters on Thursday the prosecution plans to investigate the rebellion charges against Yoon following complaints. While the president mostly has immunity from prosecution while in office, that does not extend to allegations of rebellion or treason.

The Defense Ministry said it has suspended three top military commanders over their alleged involvement in the martial law imposition. They were among those facing the opposition-raised rebellion allegations.

On Saturday, Yoon issued an apology over the martial law decree, saying he won’t shirk legal or political responsibility for the declaration. He said he would leave it to his party to chart a course through the country’s political turmoil, “including matters related to my term in office.”

Since taking office in 2022 for a single five-year term, Yoon has struggled to push his agenda through an opposition-controlled parliament and grappled with low approval ratings amid scandals involving himself and his wife. In his martial law announcement on Tuesday night, Yoon called parliament a “den of criminals” bogging down state affairs and vowed to eliminate “shameless North Korea followers and anti-state forces.”

The declaration of martial law was the first of its kind in more than 40 years in South Korea. The turmoil has sparked alarm among key diplomatic partners like the U.S. and Japan.

The scrapping of Yoon's impeachment motion is expected to intensify protests calling for his ouster and deepen political chaos in South Korea, with a survey suggesting a majority of South Koreans support the president’s impeachment. Yoon’s martial law declaration drew criticism from the conservative ruling party, but it is determined to oppose Yoon’s impeachment apparently because it fears losing the presidency to liberals.

Ruling People Power Party leader Han Dong-hun said Sunday the PPP will work with the government to determine Yoon’s early and orderly exit from office in a way that minimizes confusion, but he didn't say when that would happen. He also claimed Yoon will not be involved in state affairs, including foreign policy.

The Democratic Party criticized Han Dong-hun’s comments, saying that the exclusion of an incumbent president from state affairs isn’t supported by the constitution. It said authorities should immediately arrest Yoon and all others implicated in the case.

Yoon’s presidential office didn’t immediately respond to Han's comments.