Photo/Illutration A fund-raising party of the Abe faction in Tokyo in May (Asahi Shimbun file photo)

Prosecutors began questioning secretaries to lawmakers of the ruling Liberal Democratic Party’s Abe faction on a voluntary basis over suspected off-the-book funds generated from fund-raising parties, sources said.

The secretaries admitted to investigators from the Tokyo District Public Prosecutors Office that the lawmakers received portions of party ticket sales from the faction that exceeded the quotas assigned to them, the sources said.

Diet members belonging to an LDP faction are usually assigned quotas for selling tickets for the faction’s fund-raising parties and pass on the revenue from ticket sales to the faction.

According to sources, the faction once headed by the late Prime Minister Shinzo Abe did not list income from party ticket sales that exceeded lawmakers’ quotas in its political fund income and expenditure reports and returned the cash to individual faction members.

The faction, the largest in the LDP, did not record the money it returned in the expenditure section of its political fund reports, and faction members also did not include it in the political fund reports of their political organizations, the sources said.

The amount that went unreported, effectively constituting a slush fund, totaled more than 100 million yen ($676,000) over the past five years, the sources said.

The Tokyo District Public Prosecutors Office’s Special Investigation Department has already questioned officials of the Abe faction over a suspected failure to list items in political fund reports, a violation of the Political Fund Control Law.

The LDP faction led by former Secretary-General Toshihiro Nikai is also suspected of having failed to list more than 100 million yen in party ticket sales that exceeded quotas assigned to faction members in the income section of its political fund reports over the past five years.