An 83-year-old Indonesian witch doctor was arrested on Sunday after allegedly kidnapping a 12-year-old girl and keeping her in a cave as a sex slave for 15 years.

The witch doctor, named Jago, allegedly kidnapped “HS” as she is known when she was only 12 and put her in a cave in Tolitoli in Central Sulawesi, Indonesia, Reuters reported.

The man was said to have brainwashed the girl by convincing her he was possessed by the spirit – or jinn – of a boy named Amrin. Jago manipulated the girl into thinking Amrin was her boyfriend.

On August 5, Indonesian police rescued the now 28-year-old woman from the cave after receiving a tip-off from a neighbor, who overheard a conversation between the woman’s sister, who had known her location for a long time, and Jago’s son.

According to The Jakarta Post, the victim’s sister is married to Jago’s son. They are now being questioned by police as suspected accomplices.

In 2003, Jago allegedly took the girl and told her parents she had gone to Jakarta to work, police said. “HS” said she had been having sex with “Amrin” since 2003, adding she was also abused by the suspect. The woman was afraid to run away as she was convinced that a spirit was watching her, a local resident said.

Jago will be jailed for up to 15 years if found guilty of having violated the Child Protection Law.