Investigative authorities have decided to seek permission from the Diet to arrest Upper House member Tatsuo Tomobe in connection with a scandal involving the bogus Orange Kyosai Kumiai mutual fund, informed sources said Jan. 14. They have concluded that Tomobe was directly involved in the operation of the mutual fund, which collected 8 billion yen from more than 2,000 clients without a license from the Finance Ministry, the source said.They plan to arrest Tomobe and four other executives involved in the operation of the fund on suspicion of fraud, they said. Investigators from the Metropolitan Police Department, as well as Hokkaido and Hiroshima Prefectural Police, have formed a joint task force. While police will take action against the four executives by the end of this month, they will ask for an arrest warrant for Tomobe after the ordinary Diet session is convened on Jan. 20.Because lawmakers are granted immunity from police arrest during Diet sessions, the investigators must submit an application to a court which will then request the Upper House to approve the arrest. Tomobe has notified the Diet that he will be absent from chamber sessions because of "bad health." If the planned request for the arrest warrant is approved, Tomobe will become the 17th lawmaker to be apprehended during the Diet session in the postwar period.