Nora Anne Quoirin died two to three days, and no more than four days, from the time her body was found, the police said.
"There were no signs of sexual assault or rape. Her hymen was still intact," Negri Sembilan Police Chief, Datuk Mohamad Mat Yusop confirmed at a press conference shared live on NST Online's Facebook page.
There were scratches on her legs, but none that could lead to death.
He added that the cause of death is upper gastrointestinal bleeding due to duodenal ulcer complicated with perforation.
The condition was caused by starvation and stress.
Samples have been collected from her body for further investigations by the Chemistry Department.
Mohamad also confirmed that there were no foul play suspected in the case so far.
Search and rescue for the 15-year-old started on August 4, since she went missing from a resort in Gunung Berembun, Pantai Hills, where she was on a holiday with some family members.
Her body was found 10 days later and sent to Hospital Tuanku Ja’afar for post-mortem.
Nora Anne, who has learning disabilities, shared a room with her two siblings - Innes Julia and Maurice Arthure - at the resort they stayed in on 3 August, but was found missing the next morning.
One of the windows in the room was found partially open, but beyond that there were no other clues about her disapperance.