NHK has learned that Japanese prosecutors have asked to question on a voluntary basis the offices of former Chief Cabinet Secretary Matsuno Hirokazu and other senior members of the main ruling Liberal Democratic Party over a fundraising scandal involving its factions.

Tokyo prosecutors on Tuesday raided the offices of the LDP's Abe and Nikai factions on suspicion that they violated the political funds control law.

The factions are suspected of paying kickbacks to the offices of members who sold fundraising event tickets in excess of their quotas, without recording the amount as revenue in their political fund reports.

The Abe faction, which was once led by late Prime Minister Abe Shinzo, had paid kickbacks to most of the offices of its member lawmakers, including six top officials.

Prosecutors have been questioning on a voluntary basis the offices of the faction's lawmakers who received large amounts of money. They have now asked to question on a voluntary basis the offices of its top officials, including Matsuno.

Matsuno served as the faction's secretary-general from September 2019 through October 2021. He stepped down as Chief Cabinet Secretary last week.

The Abe faction is suspected of systematically underreporting its fundraising event revenue.

Prosecutors are looking into what the member lawmakers thought of the practice as faction officials, and as kickback recipients.