Prosecutors probing alleged tax evasion by engineering firm Mizutani Kensetsu Co. have questioned a former secretary to a retired Diet member who once served as a Cabinet minister and was a top executive of the ruling Liberal Democratic Party, according to sources familiar with the investigation.
An alleged slush fund created through the tax evasion is believed to have been used to funnel money to politicians and organized crime groups.
The former secretary, 50, is believed to have known former Mizutani Kensetsu Chairman Isao Mizutani, 61, who was arrested last month and was recently served a fresh arrest warrant over the tax evasion case.