Photo/Illutration Investigators of the Tokyo District Public Prosecutors Office seize materials from the office of Lower House member Mito Kakizawa in Tokyo's Koto Ward on Nov. 16. (Takashi Uematsu)

Prosecutors searched the office of ruling Liberal Democratic Party lawmaker Mito Kakizawa in Tokyo’s Koto Ward on Nov. 16 in a bribery investigation concerning the ward mayoral election in April.

The Tokyo District Public Prosecutors Office’s Special Investigation Department also searched the homes of Kakizawa’s aides and ward assembly members on suspicion of violating the Public Offices Election Law.

Kakizawa, a Lower House member whose constituency represents Koto Ward, is suspected of giving cash to ward assembly members to help Yayoi Kimura win the election, sources said.

Kakizawa, 52, resigned as state minister of justice on Oct. 31 for advising Kimura’s campaign to run illegal paid internet advertising in the election.

Kimura, 58, stepped down as ward mayor on Oct. 26, two days after prosecutors searched her office and home over the video ad.

Investigators also questioned a publicly paid aide of Kitazawa, one of the individuals who offered cash to ward assembly members, on a voluntary basis on Nov. 16.

In an interview with The Asahi Shimbun, Kakizawa said he provided cash to ward assembly members but insisted he had “done nothing wrong.”

He said the money was a customary mid-campaign contribution for the ward assembly election, which was held at the same time.

Prosecutors, however, suspect the money was used to bribe ward assembly members into gathering votes for Kimura in the election, sources said.

The four candidates who ran in the mayoral election included two conservatives: Kimura, a former LDP Lower House member, and Ikki Yamazaki, a former Tokyo metropolitan assembly member backed by the LDP.

Kakizawa supported Kimura’s campaign.

According to sources, the amount of cash offered to an LDP-affiliated ward assembly member is believed to have been around 200,000 yen ($1,300).

The Special Investigation Department has questioned ward assembly members on a voluntary basis about the purpose of the cash received.

The Asahi Shimbun has asked all 44 Koto Ward assembly members if they had received cash from Kakizawa’s side over the ward mayoral and assembly elections.

Three of the 40 members who responded said they received money, including an LDP-affiliated assembly member who accepted 200,000 yen from a Kakizawa aide around March.

The other two, unaffiliated with the LDP and close to Kimura, said they received 10,000 yen each.

All three said the money was a contribution during the ward assembly election campaign.

Six LDP-affiliated ward assembly members said Kakizawa or one of his aides either offered cash or asked for a meeting, but they declined.

Of the four ward assembly members who did not respond to the survey, one reported in campaign finance records for the ward assembly election a contribution of 200,000 yen received on Feb. 21 from Kakizawa’s fund management organization.

The member is affiliated with the LDP.