(Bloomberg) -- Japan’s securities watchdog filed criminal charges against a former SMBC Nikko Securities Inc. deputy president, as the trading scandal engulfing the brokerage deepened in Tokyo.

The Securities and Exchange Surveillance Commission asked prosecutors to charge Toshihiro Sato with allegedly manipulating the price of a company’s shares in relation to block offers, it said in a statement Tuesday. The SESC also filed fresh charges against SMBC Nikko and three of the brokerage’s employees, it said. 

SMBC Nikko said it sincerely apologizes for causing trouble and concern, and will cooperate with investigations and make efforts to regain trust.

Sato was arrested last month, becoming the highest-ranking executive to be embroiled in the scandal. He no longer works for SMBC Nikko. He originally hailed from the banking arm of the company’s parent, Sumitomo Mitsui Financial Group Inc. 

The fresh charges come after the SESC filed criminal complaints last month against seven SMBC Nikko employees, which didn’t include Sato, and the company itself in relation to the affair.

Tokyo prosecutors then indicted five of those individuals and SMBC Nikko.

Some of the employees involved have denied wrongdoing, according to media reports.

The SESC’s filing of charges against Sato deals a fresh blow to the reputation of SMBC Nikko, the brokerage unit of Japan’s second-largest banking group. The saga has rocked Japan’s financial industry and hurt SMBC Nikko’s bottom line, with major institutional investors and others stopping doing business with the firm.

SMBC Nikko staff are alleged to have used the firm’s proprietary trading desk to put in large buy orders for certain stocks before the market close in Tokyo. Their alleged aim was to prop up prices before the brokerage sold large chunks of those companies’ shares outside the open market for clients. 

©2022 Bloomberg L.P.