Image copyright Police handout Image caption Indonesian police published this photo of the cave

Police in Sulawesi, Indonesia say they have freed a 28-year-old woman who was held captive in a cave for 15 years by a village shaman.

The 83-year-old man is alleged to have kidnapped the woman when she was 13, and brainwashed her into believing he was possessed by a spirit or "jin".

He allegedly took her back to his home at night where he sexually abused her for more than a decade.

The man has been charged under sex abuse and child protection laws.

According to local media, the man - named as Jago - was known as an alternative healer and for performing black magic.

Police say that in 2003, the 13-year-old girl was brought to him for treatment by her own family and stayed behind with him.

Image copyright Police handout Image caption The 83-year old faces 15 years in prison if found guilty

Later that same year, she disappeared. Media reports say the shaman told the family she had left for Jakarta to find work there.

Relatives tried to find her for several years but eventually, she was declared missing.

Acting on a report, police went to the village in Galumpang, central Sulawesi on Sunday, and found the woman in a small space behind boulders.

Images released by police showed some basic furniture inside the cave, which was near the man's house.

Tolitoli Police Chief M Iqbal Alqudusy said the man had been raping the girl since she was 13 and would show her a picture of what he said was a jin who possessed him.

They allege she was brought to the man's house at night but during the day was forced to stay in the small prison-like cave.

"The victim seems to have been brainwashed, making her afraid to run away and afraid to meet other people because she was being watched by a jin," a local resident named Sugeng told the Jakarta Post.

The suspect faces up to 15 years in prison if found guilty.