Prosecutor General Lee One-seok offered an apology to the public on Monday, saying principles were not abided by when prosecutors questioned First Lady Kim Keon-hee over graft and stock manipulation allegations. 

Arriving for work at the Supreme Prosecutors’ Office in southern Seoul, Lee told reporters that he was not briefed on the interrogation by the prosecutors' office, and that it’s all his responsibility for failing to lead the prosecutors' office properly. 

Lee then vowed his best efforts to ensure the constitutional principle that all citizens are equal before the law is realized in the investigation going forward.

The head of the Seoul Central District Prosecutors’ Office, Lee Chang-soo, reportedly notified the top prosecutor of Kim's questioning at 11:10 p.m. Saturday, when the questioning was nearing an end. 

The prosecutor general said he will look into the belated report and take necessary action.

The first lady was summoned on Sunday and questioned for about 12 hours, until 1:20 a.m., at an annex building of the Presidential Security Service in Seoul over her alleged stock manipulation and luxury bag scandal.