TOKYO, Jan. 17 (Xinhua) -- Opposition lawmakers on Sunday demanded that Democratic Party of Japan (DPJ) Secretary General Ichiro Ozawa explain himself after three of his aides were arrested over financial irregularities in a 2004 purchase of land in Tokyo.

    Japanese Communist Party (JCP) leader Kazuo Shii said that he hoped to get answers to what Ozawa had been up to during the upcoming Diet session, which begins on Monday.

    Meanwhile, Liberal Democratic Party (LDP) leader Sadakazu Tanigaki said: "It's alarming the way that his aides were arrested one after the other.''

    The leader of New Komeito, the party connected to new religious organization Soka Gakkai, Natsuo Yamaguchi said "it's now in question as to how one of the country's most senior lawmakers willexplain his treasurers' financial mismanagement."

    Since Friday, three aides to Ozawa have been arrested over their role in a 400 million yen (4.4 million dollars) land purchase in Tokyo's Setagaya Ward. The purchase was not declared, leading to suspicions that the transaction involved money obtained through illegitimate means.

    Ozawa has denied any wrongdoing, and insisted he will continue to fulfil his duties in the DPJ.

    Prime Minister Yukio Hatoyama on Saturday said he would be happy for Ozawa to keep his position in the party. "Secretary General Ozawa told me that he had no intention of resigning, and Isaid that I trusted him and would like to see him continue in his current role," the prime minister said.

    Ozawa has accused the authorities of rounding on him at a key time. On Saturday, the DPJ held its annual conference. "I do not know if (prosecutors) did it deliberately, but the arrests took place at the same time as out party's convention, and I cannot accept the use of such methods by the authorities," the politician said.

    Finance Minister and Deputy Prime Minister Naoto Kan echoed those sentiments on Sunday, saying he was concerned "information on the investigation is being leaked to the media."

    Ozawa has hinted that he may ask Acting Secretary General Azuma Koshiishi to take over some of his duties in the coming months while he tackles the scandal.

    DPJ lawmaker Kozo Watanabe said he will be following events closely. "Ozawa is morally responsible because of the accusations that have been made against him," the lawmaker said. "I will be keeping an eye on him to see how he explains himself."