Police also believe she used crime novels and television programs as research. Jung's library record shows she borrowed a number of crime stories in the months before the crime.

Jung found her victim using an app for private tutors to connect with parents. She posed as a mother of a school child wanting her daughter to learn English. They both agreed that the daughter could come to the tutor's house for a consultation two days later.

Jung then bought a school uniform online to pose as the fake daughter. Once she entered the victim's home, she stabbed her with a knife.

Police said: 'Jung is short, and with the uniform on, the victim probably mistook her for a middle-school student.'

Having planned out the crime, police said Jung visited a nearby supermarket where she bought rolls of large bin bags and bottles of bleach.

Jung then cut up and dismembered her victim and placed some of her body parts in a suitcase. She then got in a taxi and dumped the suitcase in the Nakdong River in a secluded wooded area.

Police said Jung had tried to 'make it look like the victim had disappeared.'
'Jung kept the victim's mobile phone, ID card and wallet, attempting to commit a perfect crime.'

However, the taxi driver became suspicious and alerted authorities. Police retrieved the case to find blood-stained clothes. The remaining body parts were found in Jung's house.

'Jung was a loner and a recluse who has been unemployed since graduating from high school five years ago,' police said.

Jung was escorted out of the detention centre on Friday morning for prosecution. She told reporters she feels 'really sorry for the victim's family,' The Korea Times reported.

She added said, 'I think I was out of my mind,' when asked by reporters why she tried to cover up the murder.