Japanese ad giant Dentsu Group Inc., a number of other companies and a former Olympic organizing committee executive were indicted Tuesday over alleged bid rigging linked to the 2021 Tokyo Games, in the latest scandal overshadowing the legacy of the global sporting event.

Prosecutors took the decision after receiving complaints from the Japan Fair Trade Commission, indicting six companies, including Dentsu's rival Hakuhodo Inc., as well as six individuals from the companies and Yasuo Mori, former operations executive on the Tokyo Olympics organizing committee.

Photo taken on Feb. 28, 2023, shows the building housing the headquarters of Dentsu Group Inc. in Tokyo. (Kyodo)

They are suspected of violating the antimonopoly law by rigging bids for contracts worth around 43.7 billion yen ($320 million) to plan and run Olympic test events and competitions.

The officials at the six companies allegedly colluded with Mori to rig the bidding in 2018 for the rights.

Four people including Mori, 56, and former Dentsu executive Koji Hemmi, 55, were indicted after being arrested earlier this month, while the remaining three were indicted without arrest.

According to a source familiar with the case, the companies involved in making the arrangements did so primarily through Mori or Hemmi.

Dentsu Group President and CEO Hiroshi Igarashi has admitted to prosecutors that the company was involved in rigging bids for the games, sources said earlier. One of the indicted event production companies, Cerespo Co., however, has denied involvement.

"We take this situation seriously and solemnly," Dentsu said in a statement while expressing an apology for the concerns caused over the case.

The maximum fine for unreasonably restraining competition in violation of the antimonopoly law is 500 million yen.

Seiko Hashimoto, an upper house lawmaker who served as president of the now-defunct organizing committee for the Games from February 2021, said that the news of the indictments was "deeply regrettable" and that she feels "a great responsibility as the former head of the committee."

The alleged bid rigging has followed revelations of bribery in connection with the global sporting event.

Haruyuki Takahashi, a former executive of the organizing committee who was previously a senior managing director at Dentsu, has been indicted four times on charges of receiving bribes totaling around 198 million yen in return for helping companies to be selected as Olympic sponsors or marketing agents.

The latest development means that the number of people indicted over the bribery case and the latest scandal has come to 22.

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