Prosecutors have questioned ruling Liberal Democratic Party lawmaker Kentaro Sonoura on a voluntary basis on suspicion of underreporting some 40 million yen ($296,000) in political funds, sources close to the matter said Tuesday.

Kentaro Sonoura. (Kyodo)

The latest in a recent series of scandals involving LDP lawmakers comes as Prime Minister Fumio Kishida, who heads the party, has been struggling with falling public support for his Cabinet.

The prosecutors are focusing on whether Sonoura, 50, a fifth-term House of Representatives member, was aware of the underreporting, the sources said. One of his secretaries, who was questioned earlier this summer, admitted to having informed him about it.

Sonoura last month told reporters he was unaware of the underreporting and denied any knowledge of what the secretary claimed.

The organization that manages Sonoura's political funds reported it had received 43.62 million yen from six fundraising parties held between 2018 and 2020. Sonoura heads the body, while the secretary serves as its treasurer.

A different support organization for Sonoura separately reported it had raised some 10 million yen through three parties held between 2017 and 2019.

The two bodies are suspected of underreporting by a total of around 40 million yen, the sources said.

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