Business suit retailer Aoki Holdings Inc. paid 500 million yen ($3.7 million) for its sponsorship deal with the Tokyo Olympic and Paralympic organizing committee, less than half of what it cost other companies for similar arrangements, sources familiar with the matter said Thursday.

The sources also said the same day that Haruyuki Takahashi, a former Tokyo Olympic organizing committee executive who had significant influence in sports circles, is suspected of leading the decision to select the suit company as a sponsor more than a year before the official announcement.

The Tokyo District Public Prosecutors Office's special team is investigating the case as an irregular "top-down" decision to choose a sponsor that allegedly arose from a request by Hironori Aoki, the retailer's former chairman.

Combined photo shows Haruyuki Takahashi (L) and Hironori Aoki. (Kyodo)

The revelations came a day after Takahashi, Aoki and two others were arrested on bribery allegations.

Aoki Holdings released a statement Wednesday in the wake of the arrests saying it would cooperate with the investigation by prosecutors.

Hironori Aoki's younger brother, Takahisa Aoki, and Katsuhisa Ueda, an executive director of the firm, are also suspected of repeatedly requesting Takahashi give Aoki preferential treatment in the process of selecting sponsors from January 2017 to June 2021.

Sponsors, which held contracts with the organizing committee, were divided into separate categories -- "gold partner," "official partner" or "official supporter" -- depending on the amount they paid.

Aoki was categorized as an "official supporter" for the Tokyo Games held in 2021 after a one-year delay due to the COVID-19 pandemic. The standard fee for a sponsor at that tier was approximately 1.5 billion yen, sources said.

The upper-level "gold partners" paid roughly 15 billion yen.

Neither the process of sponsor selection nor the contract fees have been released.

By sealing an "official supporter" contract, the retailer was allowed to use the games' emblems for business purposes and sell licensed products.

Aoki was found to have allocated some 250 million yen in additional funds toward "strengthening athletes," of which about 230 million was transferred to Takahashi's consulting company.

Takahashi is a former senior managing director of Japan's largest advertising agency Dentsu Inc., which served as an exclusive agent for Olympic sponsorships.

Dentsu essentially acted as a selection panel while also pitching potential sponsors and contract values to the organizing committee's marketing division where many staff seconded from Dentsu were working.

Takahashi reportedly told investigators during questioning that he approached Aoki with a proposal to sponsor the games. He connected the retailer to an executive in the marketing division after the firm said it was interested in the deal if "fees were cheap."

The former organizing committee executive has denied involvement in bribery, although he acknowledged receiving money, according to investigative sources.

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