The teenager laid a charge of rape last month and alleged that she was walking in the street in Esangweni Section when she was attacked.
Police say she said she was approached by her boyfriend who ordered her to come with him to his house and she refused.
"She said the boyfriend threatened to kill her and she screamed for help before he threatened with her knife he was carrying," said police spokesperson constable Tebogo Sesing.
"She then walked with him to his place where he locked the door and raped her. After raping her he poured cold water over her body."
"He then released her and threatened to kill her if she reported the matter but she came straight to the police station and laid a charge of rape."
The 20-year-old man was later arrested and detained at the Thembisa police station.
"Police interviewed the complainant for the second time and she confessed that her mother forced her to open the case and that she was still dating the accused," said Sesing.
The young man was yesterday released and the girl was arrested. She is expected to appear in the Thembisa magistrate court soon.
- So why isn't the MOTHER being arrested as well?
"We will not tolerate people reporting false cases," said Thembisa station commander Brigadier Msesenyane Manganyi.
"It is a waste of time and resources. Anyone who will be found to be doing that will be brought to book. We appeal to the community to work with us to fight against crime."