“We need to investigate former president Lee to find the truth (in the scandal) in a transparent and effective manner,” Yonhap news agency quoted an unnamed Seoul prosecutor as saying.

Allegations of corruption involving the 76-year-old’s relatives and aides during his 2008-2013 presidential term have mounted in recent weeks.

Seoul prosecutors have been investigating multiple cases of bribery amounting to millions of dollars, with the net closing in around the former leader.

His successor Park Geun-Hye was ousted last year over a massive corruption scandal that emerged in 2016.

The verdict in her trial on charges of bribery and abuse of power is due next month, with prosecutors demanding 30 years in jail.