Japan's ruling party powerbroker Ichiro Ozawa hit back on Friday as he battles a campaign finance scandal, by suing the government in a bid to stop an indictment against him.
Ozawa, a former party chief and the biggest faction boss of the Democratic Party of Japan (DPJ), is a veteran backroom operator and in September narrowly failed in a bid to oust Prime Minister Naoto Kan.
The 68-year-old dubbed the "Shadow Shogun" of Japanese politics has long been dogged by a campaign finance scandal that has seen three of his former aides indicted and has led prosecutors to raid his offices.
In the long-running legal saga, a citizens' review panel last month forced the judiciary to once more take up the case against Ozawa after prosecutors earlier dropped it citing a lack of evidence.
Ozawa on Friday called that decision "illegal and invalid" in a suit filed with the Tokyo District Court, according to his lawyers.
The scandal centres on false accounting reports in 2004 and 2005 by the body that manages Ozawa's campaign funds.
The opposition has attacked the DPJ, alleging it is trying to protect Ozawa, the controversial strategist credited with engineering the DPJ election win in August 2009 that ended more than half a century of conservative rule.