Four former executives of Dai-Ichi Kangyo Bank pleaded guilty Monday to extending illegal loans to a "sokaiya" corporate extortionist in violation of the Commercial Code, in their first trial hearing before the Tokyo District Court.The four, all wearing navy-blue suits and white shirts, are former Vice President Tsuneo Uchida, 60; Hiroshi Inotsume, 55, a former managing director in charge of general affairs; Tatsuo Shibuya, 53, former head of the bank's general affairs department; and Kenji Tanaka, 59, a former senior managing director.The four are suspected of conspiring to provide sokaiya Ryuichi Koike, 54, with loans totaling 11.78 billion yen on 52 separate occasions from July 1994 through September 1996 to buy his silence at the bank's annual shareholders' meetings in 1995 and 1996.The four defendants admitted in Monday's court session that the information cited by prosecutors is essentially correct. But their lawyers hinted that they may contest the prosecution's allegation that the loans, which were made through a nonbank affiliate to a company run by Koike's brother, amounted to "financial benefits" to Koike.The Commercial Code bans firms from giving financial benefits to sokaiya. The four also apologized for causing turmoil. Eleven former DKB executives have been indicted for alleged violations of the Commercial Code over the bank's loans to Koike.Prosecutors have divided the 11 defendants into three groups. The first hearings for defendants in the other two groups, including former Chairman Tadashi Okuda, are expected Wednesday and Friday. According to the indictment, the four, conspiring with other DKB executives who are to be arraigned later this week, allegedly made the loans to Koike through Daiwa Shinyo, a nonbank moneylender affiliated with the bank.The loans were paid out to Kojin Building, a firm run by Koike's younger brother, Yoshinori, prosecutors said. Of the 11.7 billion yen loans to Koike, Uchida and Inotsume are accused of conspiring to pay 8.88 billion yen, Shibuya is blamed for 7.02 billion yen and Tanaka for 3.78 billion yen. The bank reportedly began providing loans to Koike in 1985 and had outstanding loans of 8.8 billion yen as of September 1992. Prosecutors allege that the bank continued lending money to the influential racketeer even though the loans were not backed up by enough collateral.