The eldest son of the Lotte Group founder said Thursday he has sued the chief of Lotte Holdings Co. for the head's role in driving him out, waging a sideline attack against his younger brother as part of a long-running sibling power struggle.

Lotte, South Korea's fifth-largest conglomerate, is mired in a leadership dispute between group founder Shin Kyuk-ho's two sons -- Dong-joo and Dong-bin -- who had each controlled the company's operations in Japan and Korea until earlier this year.

While Dong-joo was ousted from 26 key positions at Japanese units between last December and January this year, Dong-bin took the helm of Tokyo-based Lotte Holdings, the group's holding firm, after winning support from Japanese shareholders in August.

Holding a press conference at a hotel in Tokyo, the eldest son said he has filed a lawsuit against Takayuki Tsukuda with the Tokyo District Court, claiming the chief provided incorrect and exaggerated information on him to his father over the course of his dismissal.

"(Such false reports) constitute a serious violation of relevant rules as they were aimed at eliminating me," the eldest son said, stressing that such an unfair means hurt the transparency of the whole company.

It is widely seen as a sideline attack against his younger brother, as Tsukuda has teamed up with Dong-bin.

Noting that his father agreed to the suits, which are "due steps to bring Lotte back to normal," the scion also urged his brother to "fight with Tsukuda and other Japanese board members of Lotte Holdings," rather than having conflict between the siblings.

The elder son also said he has filed a separate case against four group units -- Lotte Co., Lotte Corp., Lotte International Co., and Lotte Real Estate Co. -- to seek compensation for damages. (Yonhap)