Tenom police chief Hasan Majid said initial investigations showed that the 18-year-old suspect had consistently raped the girl for three years, with the latest incident taking place last month.
He said she was initially afraid to tell anyone about her predicament for fear that her brother would get angry with her.
However, following the most recent incident, she could no longer bear it and told her schoolteacher about her experience.
“After confiding in the teacher, the girl told the mother who then accompanied her to lodge a police report yesterday.
“Following that, we detained the suspect, who is a secondary school student in Tenom, at his house at 8.50pm,” he said, when contacted.