SEOUL, South Korea (AP) — Police are considering placing an overseas travel ban on South Korean President Yoon Suk Yeol over his imposition of martial law last week, Yonhap news agency reported Monday.

The report said police were considering banning Yoon from leaving the country as they are investigating Yoon’s martial law imposition last week. Repeated calls to police were unanswered.

South Korean prosecutors on Sunday detained former Defense Minister Kim Yong Hyun who allegedly recommended last week’s brief but stunning martial law imposition to Yoon, making him the first figure detained over the case.

Yoon avoided an opposition-led bid to impeach him in parliament on Sunday, with most ruling party lawmakers boycotting a floor vote to prevent the two-thirds majority needed to suspend his presidential powers.