Tokyo prosecutors on Thursday searched the home and the Diet office of House of Representatives member Mito Kakizawa, with a special investigation team also seeking to question him over allegations of vote-buying in a Tokyo ward mayoral election in April, investigative sources said.

The 52-year-old, who on the same day left Japan's ruling Liberal Democratic Party, is suspected of paying money to several Koto Ward assembly members to get a mayoral candidate he backed elected. His constituency office has already been searched, and prosecutors will decide whether to press charges after confirming his involvement.

Officials of the Tokyo District Public Prosecutors Office head to Liberal Democratic Party lawmaker Mito Kakizawa's home in Tokyo's Koto Ward on Dec. 14, 2023. (Kyodo)

The development comes at a time when criticism of the LDP has been growing amid a series of political fund scandals involving senior government and party officials belonging to the largest faction, formerly led by slain Prime Minister Shinzo Abe.

Kakizawa has denied any intent to bribe, asserting the money was provided as a customary mid-campaign contribution ahead of a ward assembly election also held in April. But prosecutors suspect he intended to buy votes for Yayoi Kimura in violation of the election law.

According to sources familiar with the matter, Kakizawa told his secretaries and others in February to evenly distribute 200,000 yen ($1,400) among the ward's assembly members. While some declined the money, around five people are believed to have accepted it, while others who initially took it later returned it.

Updates were provided to Kakizawa through a coordinating secretary, according to the sources.

Several secretaries and assembly members have been questioned regarding the matter, and prosecutors are investigating whether those who accepted the money acted in support of Kimura.

The son of a former foreign minister, Kakizawa resigned as senior vice justice minister in late October after admitting that he had proposed using an online advertisement in Kimura's campaign, which is prohibited by the election law.

Kimura, who stepped down as mayor in November after using the paid advert on YouTube to urge people to vote for her, previously served as an LDP lower house lawmaker.

Violators of the public offices election law regarding vote-buying face imprisonment of up to three years or a fine of up to 500,000 yen. Under the same law, those who use paid advertisements online for specific candidates face imprisonment of up to two years or a fine of up to 500,000 yen.

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