Exchange officials have announced vague plans to increase the daily volume of the new system to as much as 8 million trades later this year. Suzuki will have to determine how much the system should be expanded and set a time frame for the upgrade.

CEO, other top execs arrested at portal firm

TOKYO -- Three top executives of Internet portal operator Livedoor Co. were arrested last week for allegedly violating Japanese securities laws.

The arrests came a week after law enforcement officials raided the offices of Tokyo-based Livedoor and several affiliated companies. The raids caused investors to panic, leading to a flood of online trading that played a major role in stressing the systems at the Tokyo Stock Exchange.

The Tokyo District Prosecutors' Office arrested Livedoor CEO Takafumi Horie as well as the company's chief financial officer and the president of its Livedoor Marketing Co. subsidiary. Horie stepped down after his arrest and was replaced as CEO by Kozo Hiramatsu, who had been a senior vice president at the company.