Vienna - Austrian incest suspect Josef Fritzl has said he was "born to rape," according to a report by a court-appointed psychiatrist who probed the mind of the man who had kept his his daughter locked in a dungeon for 24 years.

"I have found out that I possess a malicious streak," 73-year-old Fritzl told psychiatrist Heidi Kastner, according to parts of the report published by the Kronen Zeitung newspaper on Wednesday.

Fritzl is set to go on trial in the coming months for allegedly raping his daughter Elisabeth Fritzl many times while keeping her in the dungeon he built below his house in Amstetten, around 130 kilometres west of Vienna.

Elisabeth gave birth to seven children by him while in captivity.

Fritzl claimed he was an unwanted child who was often beaten. He told the psychiatrist that he was convinced his daughter would be his property as long as she lived.

Kastner said Fritzl's house reflected his perverted mind: While living a relatively normal life with his wife upstairs, he went down to the cellar to act out his "evil side".

Telling his wife that their daughter had run away, he pretended that three of the children born by Elisabeth had been left at the family doorstep by her.

Three other children had to grow up in the dungeon. One died shortly after birth.

Although Fritzl was certifiably sane and could be held responsible for his actions, "he has a severe psychological disorder," prosecution spokesman Gerhard Sedlacek told Deutsche Presse-Agentur dpa.

Therefore, the prosecutor would request that the suspect should be imprisoned in an institution for mentally anomalous delinquents. (dpa)