A former secretary of Yukio Hatoyama repeatedly tried to balance the books by faking profits around every January, sources said, providing the first glimpse into details of shady accounting practices by the prime minister's fund management body.

It has also been revealed that more than ¥100 million was falsely declared out of revenues from selling tickets for fundraising parties between 2004 and 2008, the sources said, and that it now looks like at least ¥300 million was falsely declared in the body's financial statements.

The Tokyo District Public Prosecutor's Office has already questioned the former government-paid secretary, who was dismissed by Hatoyama in June, on a voluntary basis and is expected to indict him without arrest on charges of violating political financing laws.