A 60-year-old man, who had sex with his daughter, told religious department officers that incest was permissible because she had taken a vow of slavery, Harian Metro reported.
The tabloid said the man and his daughter, in her 30s, were caught by the Federal Territory Islamic Department (Jawi) officers at a hotel in Jalan Putra, Kuala Lumpur, at 1am on Wednesday.
The man was in shorts while his daughter was naked under the sheets when the officers raided the room.
"The man brazenly said his partner was his daughter who lived in Medan, Indonesia, with his second wife, who is an Indonesian," a source was quoted by the newspaper.
"The officers believe the father and daughter had already had sex based on condoms and sex pills found in the room."
During interrogation, the man said he slept with his daughter because it was "permissible" according to religion.
He claimed that his religious teacher in Indonesia had told him that the daughter only needed to recite a vow of slavery three times and she would be "halal" to have sex with her family members if she allowed it.
The case is still under investigation and the man is currently out on bail.