Public prosecutors raided the office of Tokyo's Koto Ward mayor on Tuesday over a suspected violation of the public offices election law by the mayor.

According to people familiar with the matter, Yayoi Kimura, who was elected as Koto mayor in April, is believed to have played a part in paid online campaigning for the election, an act prohibited by the law. Kimura herself appeared in a campaign advertisement on social media.

In response to a criminal complaint filed by local residents against the mayor, the special squad of the Tokyo District Public Prosecutor's Office searched the office for evidence for some four hours until around 12:50 p.m., the ward government said.

At a news conference in August, Kimura said the ad in question was posted by her supporters.

"I told them to abide by the public offices election law," she noted. Kimura denied any intention to resign, saying, "I will make efforts to comply with laws and regulations."

Kimura was a House of Representatives lawmaker for the ruling Liberal Democratic Party between 2014 and 2021.