A former senior official of the organizing committee for the 2020 Tokyo Olympics and Paralympics has admitted to bid-rigging charges.

The former deputy executive director of the committee's operation bureau, Mori Yasuo, was indicted in February this year. Prosecutors accused him of violating the anti-monopoly law by pre-arranging the winners of bids related to the Games and their test events. The contracts reportedly totaled 43.7 billion yen, or roughly 300 million dollars.

The investigators also say several firms, including major ad company Dentsu Group, were involved in the bids.

During the first hearing of his trial at the Tokyo District Court on Wednesday, Mori admitted to the accusation.

According to prosecutors, Mori felt a sense of urgency as preparations were not making progress and sought the assistance of Dentsu. They also said the ad agency viewed this cooperation as an opportunity to secure Games-related contracts and expand its sports business.

The prosecutors said Mori thought it would be difficult to award contracts to Dentsu alone and wanted to include other firms.

When questioned, Mori said he had wanted to ensure the success of the Games. The defendant said he wonders whether the Games would have been possible without pre-arrangements of the bids. Nonetheless, he said his act cannot be justified and he cannot make excuses.

In relation to the bid-rigging scandal surrounding the Tokyo Games, six companies, including Dentsu Group, and six of their executives have also been indicted. Mori is the first to stand trial in connection with the scandal.