Informed sources say Tokyo prosecutors have searched the office of a former state justice minister on suspicion of vote buying for a mayoral candidate in his constituency.
The prosecutors raided the office of Kakizawa Mito on Thursday. They also searched the homes of his secretaries and assembly members of Tokyo's Koto Ward.
Kakizawa is a Lower House member from the main governing Liberal Democratic Party. But he backed Kimura Yayoi, who won the mayoral election in April. Kimura beat out a candidate supported by the LDP, as well as two others.
It's believed that Kakizawa's secretaries and supporters managed Kimura's campaign.
Sources say his secretaries offered cash to more than 10 assembly members before the poll. They say some of them received cash worth between around 70 dollars and 1,340 dollars.
People associated with Kakizawa and the assembly members who accepted the money deny any illegalities. They say the payments were gifts, and not vote buying.
Investigators are interviewing the secretaries who allegedly handed over the money.
Kakizawa was appointed State Minister of Justice in September, but stepped down in late October to take responsibility for proposing that the Kimura campaign use paid online ads. Such ads violate the public offices election law.
Kimura has also resigned from her post as mayor.