South Korea's ex-defence minister arrested over alleged role in martial law

South Korean prosecutors have arrested ex-Defence Minister Kim Yong-hyun over his alleged role in President Yoon Suk-yeol's declaration of martial law, Yonhap News Agency said.

The prosecution's special investigative team has questioned Kim, who voluntarily appeared at the Seoul Central District Prosecutors' Office at around 1:30 am on Sunday (1630 GMT on Saturday), the report said.

Kim faces a travel ban as prosecutors investigate, Yonhap said.

The national police are also investigating claims of treason against Yoon and top ministers.

Kim had already resigned as defence minister after the brief suspension of civilian rule late on Tuesday.

Yoon survived an impeachment vote by opposition parties due to a near-total boycott by his People Power Party (PPP).

The PPP said after the vote that it had blocked the impeachment to avoid "severe division and chaos", adding that it would "resolve this crisis in a more orderly and responsible manner".

'Anxiety and inconvenience'

The opposition has already vowed to try to impeach Yoon again as soon as Wednesday, and many protesters vowed to continue demonstrations next weekend.

"I will impeach Yoon Suk Yeol, who has become the worst risk for South Korea, at any cost," opposition leader Lee Jae-myung said.

Before the vote, Yoon, 63, had apologised for the turmoil but said he would leave it to his party to decide his fate.

"I caused anxiety and inconvenience to the public. I sincerely apologise," he said in the televised address, his first public appearance in three days.

He said he would "entrust the party with measures to stabilise the political situation, including my term in office".

The backing of PPP lawmakers came despite party head Han Dong-hoon — who was allegedly on an arrest list on Tuesday night — saying Yoon must go.

Only three PPP lawmakers — Ahn Cheol-soo, Kim Yea-ji and Kim Sang-wook — voted in the end.