The Nikkei 225 index at the Tokyo Stock Exchange fell 111.58 points to 8,655.51. The Topix index of all first-section issues lost 1.66 percent, or 12.46 points, to 738.03. Olympus fell 29 percent to close the session at a 16-year low of 734 yen after the firm admitted gross mismanagement of its fund to cover massive losses. In the latest step of an expanding scandal, the company said a panel investigating alleged overpayments in past takeovers found that funds had been used to cover losses on investments dating back to the 1990s. "This is denting Japan's reputation among overseas investors," said Hideyuki Ishiguro, supervisor at investment strategy at Okasan Securities.