Investigators carried out a raid on the homes of the chairman and the president of Yamaichi Securities Co. in Tokyo on July 31 over the alleged payoffs by the brokerage to a corporate racketeer.

The homes of President Atsuo Miki and Chairman Tsuguo Yukihira, as well as more than 20 other locations were searched. Sources say both Yukihira and Miki will submit their resignations soon to take responsibility for the Big Four firm's involvement in the scandal. Yukihira is also the current chairman of the Japan Securities Dealers Association.

The search follows a raid July 30 on Yamaichi's head office in Tokyo. Homes and offices were searched by investigators from the Tokyo District Public Prosecutor's Office and the Securities and Exchange Surveillance Commission and included those of former and current executives of the company's general affairs department, as well as other equities- and sales-related departments. Sources say the investigators will scrutinize the materials taken to find whether any business or political figures received favors from Yamaichi, which is the smallest of Japan's Big Four brokerages.

Yamaichi is suspected of having provided at least 80 million yen in illegal financial favors to Ryuichi Koike, 54, the racketeer at the center of payoff scandals also connected with Dai-Ichi Kangyo Bank and Nomura Securities Co., officials said.