TOKYO - Japanese police on Monday raided locations related to a minor political group for allegedly obstructing campaigns in a recent parliamentary by-election in Tokyo, local media reported.

Tokyo's Metropolitan Police Department suspected that the group "Tsubasa no To" disrupted speeches by opponents in the lower house by-election last month, after receiving complaints from several other camps in the race, Kyodo News reported, citing investigative sources.

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The searches covered the office of the group and the homes of its leader Atsuhiko Kurokawa, 45, and Ryosuke Nemoto, 29, who was fielded by the group in the April 28 election for the Tokyo No. 15 constituency for the House of Representative but lost.

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The two, along with another in their camp, allegedly used loudspeakers to interrupt rivals' campaigns and chased after other camps' vehicles, disrupting traffic, according to the report.

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Under the law, those who obstruct speeches or rallies of candidates in an election campaign could face imprisonment for up to four years or a fine of up to 1 million yen ($about 6,400), Kyodo News said.