The prosecution has secured testimonies indicating that Jang Yoon-gi, the perpetrator who murdered a high school girl in Gwangju, frequently made remarks about "kidnapping a high school girl" since his own high school days.

Prosecutors view this as evidence supporting the charges of rape and murder against Jang.

Following a digital forensic analysis of a spare mobile phone that Jang had in his possession when he was apprehended by police on May 5, the prosecution recovered social media conversations he had with a classmate starting from the winter break of 2019, when he was a first-year high school student.

It is reported that the conversations included statements from Jang such as, "I want to kidnap a high school girl," and "I can just kidnap one with a van."

The prosecution also summoned the classmate who was the recipient of these messages and secured a statement confirming that "Jang frequently talked about kidnapping high school girls."

To prove Jang's intent and planning for sexual crimes, as well as his abnormal sexual perception, the prosecution has requested two high school classmates and two former colleagues from his time as a public service worker to testify in court.

Two days before murdering the high school girl, Jang received a warning text message from the police for stalking a Vietnamese woman. He then threw his mobile phone into a stream and switched to a spare phone without a SIM card that he had used in the past.

During the initial police investigation, he claimed the murder was "accidental," concealing his intent to commit sexual assault. However, the old, empty phone he switched to ended up becoming the key evidence that revealed the charges of rape and murder.

Furthermore, traces were found on this phone showing that after the crime, while connected to Wi-Fi, Jang searched for terms such as "fainting if hit in the neck" and "blunt weapon."

Regarding this, it is reported that Jang stated, "I searched for those terms because I felt sorry for using a weapon."

During the police investigation, Jang initially claimed, "I stabbed the person without knowing if it was a woman or a man." Later, during the prosecution's investigation, he reportedly said, "I thought the victim was a female college student," and "I would not have committed the crime if I had known she was young."

Previously, while attending a warrant validity hearing at the Gwangju District Court on May 7, Jang responded to reporters' questions about why he attacked the student and whether it was a planned crime by claiming, "I didn't know she was a high school student," and "I did not plan it."

However, after it was revealed that the police had systematically covered up the connection to sexual crimes, Jang eventually admitted to all charges of rape and murder brought by the prosecution during a trial held on July 13.

Reported by Kim Minjeong | Video by Choi Gang-san | Graphics by Yang Hye-min | Produced by SBS Digital News