Prosecutors on Friday handed the teenager suspected of murdering and dismembering her classmate last July to the Sasebo Police Station in Nagasaki Prefecture for safekeeping while she awaits her family court trial and potential criminal charges.
Prosecutors have completed psychiatric tests on the 16-year-old, whose alleged dissection of her school friend shocked the nation.
Suspects under 20 must be sent to family court because they are minors. If criminal prosecution is deemed necessary, the court can turn the minor back over to the prosecutors.
Based on the girl's accounts and psychiatric tests, the prosecutors believe she can be held criminally liable for the July 26 slaying of her 15-year-old classmate, investigative sources said.
The girl allegedly strangled the classmate and mutilated the corpse after inviting her to her apartment in Sasebo, where she lived by herself. She was arrested shortly afterward.
Until Friday she was being held at a medical facility, for psychiatric evaluation.
Now that she is in police custody, she will undergo questioning before being taken to the family court, the sources said.
Before handing her over to the court with their recommendation, the prosecutors will determine whether the case merits criminal prosecution.
In serious crimes, a juvenile can be held criminally liable instead of being placed under supervision. The minor would thus be tried as an adult.