Prosecutors have begun questioning, on a voluntary basis, people who were listed as donors to Prime Minister Yukio Hatoyama's fund management body in connection with false statements in his political funds reports, sources familiar with the case said.

The investigators are also expected to question one of Hatoyama's former secretaries, the sources said.

The fund management body's financial statements listed contributions that were made by individuals who were already dead and people who denied ever making donations.

The issue came to light before Hatoyama's Democratic Party of Japan took power in the Aug. 30 general election.

On June 30, Hatoyama said there were false entries related to donations from about 90 people totaling ¥21.77 million in the political funds reports for 2005 to 2008, and blamed his former secretary for the statements.

The prosecutors began investigating the allegations after an unnamed group filed a criminal complaint with the Tokyo District Public Prosecutor's Office in July against Hatoyama, the former secretary and a person in charge of accounting.