The defense counsel for a 17-year-old boy charged with hijacking a bus on May 3-4, murder and attempted murder has asked the Saga Family Court to conduct formal psychiatric tests on the youth, sources close to the case said Thursday.

The counsel, which comprises three lawyers belonging to the Hiroshima Bar Association, filed a 10-page petition Wednesday requesting the tests.

The boy's case was transferred Wednesday to the Saga Family Court following a decision by the Hiroshima Family Court that the former facility is in a better position to handle the case because the youth is from Saga and the details of his life there must be scrutinized.

The Saga Family Court decided Wednesday to appoint five court investigators to conduct a detailed study of the boy's psychological state and physical condition by interviewing the boy's family members, school officials and doctors at the hospital where he had been hospitalized, sources said.