Tokyo - The office of Ichiro Ozawa, president of Japan's main opposition party, the Democratic Party of Japan, received a total of 200 million yen (2 million dollars) in allegedly illegal corporate donations from the Nishimatsu Construction Company over 10 years, Japanese media said on Thursday.

The case of allegedly illegal corporate donations has stirred the nation's political scene and damaged Ozawa's chances of becoming the next prime minister in an election slated for this autumn, Japan's daily newspaper The Asahi Shimbun said.

The mid-sized construction company was suspected of donating about 25 million yen every year since 1995 to Ozawa's office, Rikuzankai, to win construction bids for public works in the northern area, where Ozawa is based.

Since Japanese law prohibits political offices from receiving corporate donations, state prosecutors on Tuesday arrested Ozawa's secretary, Takanori Okubo, on suspicion of violating the political funds control law.

Okubo, who has denied the charges, was suspected of forging reports of donations provided by dummy political groups established by former Nishimatsu executives.

After his secretary's arrest, Ozawa at a press conference accused the prosecutors' office as abusing "state or prosecutorial authority" at a time when an early general election was being considered. Ozawa's party members called it a political conspiracy.

"Such a thing should not happen in a normal democratic society," The Asahi Shimbun quoted Ozawa as saying at the press conference.

The news has rocked Ozawa's party, with some members hoping their leader will step down and others trying to show solidarity in difficult times, media reports said. (dpa)