Prosecutors launched an investigation Wednesday into allegations that a son of a major South Korean conglomerate head attacked lawyers while he was drunk at a private dinner two months ago, the Seoul office said the same day.

The Seoul Central District Prosecutors' Office said it has assigned the case to a criminal investigation unit, after reviewing the complaint filed by the Korean Bar Association a day earlier.

Kim Dong-seon, the third and youngest son of Hanwha Group Chairman Kim Seung-youn, is suspected of physically and verbally assaulting some associate lawyers from a top law firm while he was intoxicated at a social dinner in September. 

Kim Dong-seon, the youngest son of Hanwha Group Chairman Kim Seung-youn, is shown in this file photo from March 8, 2017. (Yonhap)
He slapped some of them in the face, yanked their hair and made patronizing remarks such as "Speak to me in honorifics," "Stand upright (in front of me)" and "What does your father do for living?"

Hanwha is the eighth-largest family-controlled conglomerate in Korea. It is also a client of Kim & Chang, the law firm to which the lawyers belong.

Kim has apologized for the misbehavior through his father's company. Kim, who had worked at Hanwha's construction affiliate as a manager, quit after he was convicted for similar assault charges early this year. In January, he got into altercations with guests at a bar, again while he was drunk. He was given a suspended jail term in March. (Yonhap)