Prosecutors have also raided the office of advertising giant Dentsu, Kyodo reported. Takahashi is a former executive of Dentsu Inc, a wholly owned subsidiary of Tokyo-listed Dentsu Group Inc, which said it was cooperating with prosecutors. Reuters was unable to contact Takahashi.

The investigation is looking into whether payments of 45 million yen ($325,544) between 2017 and 2021 to a company run by Takahashi violated a law that prohibits public servants from taking money in relation to their positions, local media has reported.

Board members of the Olympics organising committee were considered quasi-public servants. Aoki became an "official supporter" for the Tokyo Games, providing referee uniforms and selling suits sporting the Olympic emblem.

(Reporting by Sakura Murakami, Sam Nussey and Rocky Swift; Editing by Christopher Cushing, Himani Sarkar, Frank Jack Daniel and Mark Heinrich)