The Sasebo Summary Court has extended the detention period for a 16-year-old girl until Dec. 24 so that she can undergo further psychiatric tests, after the teen was arrested in July on suspicion of killing a classmate and dismembering her body, local prosecutors said.

Prosecutors applied on Wednesday to prolong the girl's three-month detention, which had been scheduled to end next Monday. The court granted their request later on Wednesday.

The girl is being held at a medical facility for psychiatric evaluation to examine whether she can be held criminally responsible for the July 26 murder of her 15-year-old female classmate.

She is alleged to have strangled the classmate to death and mutilated the corpse at her apartment in Sasebo, Nagasaki Prefecture, where the suspect lived by herself.

The prosecutors had requested an extension of the detention period following the Oct. 5 suicide of the girl's father, which distressed the suspect.

The teen's lawyer said it is not desirable to detain her for a long time, but the extension is unavoidable given the seriousness of the case.