The corruption case involving a powerful former Tokyo Olympics organizing committee executive continued to widen Monday, with prosecutors raiding the offices of Osaka-based advertising firm Daiko on suspicion of bribery.

The raid came as the Tokyo District Public Prosecutor’s Office announced it was looking into allegations that Daiko provided at least ¥14 million to a firm run by an acquaintance of Haruyuki Takahashi, 78, a former organizing committee official who ran his own consultancy firm, in exchange for favorable treatment. Neither the firm nor the acquaintance have been publicly named, but a portion of the money is believed to have been transferred to Takahashi.

Takahashi has already been arrested on suspicion of receiving a total of roughly ¥51 million from former Aoki Holdings chairman Hironori Aoki and two company executives, with prosecutors believing the payments were made in order to ensure the company was named as the official supplier of the formal uniforms worn by Japanese Olympics and Paralympics athletes and officials at last year’s Games. Takahashi denies the charges.