Josef Fritzl kept his ailing mother locked in an attic room with bricked-up windows until her death while downstairs he prepared the cellar dungeon in which he imprisoned his daughter, reports claimed yesterday.

Fritzl, 73, is awaiting trial for raping and incarcerating his daughter Elisabeth in a purpose-built prison beneath his home in the town of Amstetten, where he fathered seven children with her during her 24 years of captivity. One of the children, a baby boy called Michael, died shortly after birth and Fritzl is said to have burnt his body in an incinerator.

Leaked court papers said that shortly before he locked up his daughter, the retired engineer and property developer imprisoned his mother in the attic of her own house and bricked up the windows to block out any daylight. He said it was revenge for the abuse that he claims to have suffered at her hands growing up. She died in 1980.

“I never received any love from her. She beat me and kicked me until I was lying on the floor bleeding. I had a horrible fear from her,” Fritzl told a court psychiatrist. “She kept insulting me and told me I was a Satan, a criminal, a no-good.”

The quotes are extracted from a report by a forensic psychiatrist who examined Fritzl during six in-depth sessions. The confidential report, in which the psychiatrist declared Fritzl sane and fit for trial despite suffering from a “combined personality disorder”, was leaked to the Austrian press ahead of the trial, which is expected to begin in January.

According to the report, Fritzl’s mother worked as a servant while raising him alone after an acrimonious divorce. Fritzl claims that she beat him and isolated him from other children. Fritzl continued to live in his mother’s house in Amstetten, where he brought his wife and had seven children by her. He then locked his elderly mother in the attic until her death. By then Fritzl had already begun building the concrete bunker in his cellar with the purpose of imprisoning Elisabeth, now 42. He lured her into the dungeon and locked her up in 1984.

Three of the children whom Fritzl fathered with Elisabeth lived in the large upstairs apartment with him and his wife, Rosemarie, 69. The children aged 12 to 15 had a normal life and went to school, while their three siblings, aged 5 to 19, were kept in the dank cellar with their mother, never seeing the light of day until they were freed by police on April 26 this year.

According to the psychiatrist’s report, Fritzl felt dissatisfied with his wife. “She [Rosemarie] became fat and I didn’t like that,” he said. Instead, he turned to his daughter, whom he raped repeatedly over decades.

Fritzl believed himself to be a good father to his incestuous family. “The sons and daughters I had with Rosemarie gave me little physical affection,” he said. “But the three children I had with Elisabeth and raised upstairs were very kind to me. Also the children in the cellar were extremely affectionate towards me.

“In any event, I always took very good care of the whole of my offspring,” he told the psychiatrist. Fritzl recalled taking games and toys to the dungeon, and allowing the children to keep a budgerigar and a goldfish. “When I was with them we would all sit together and talk or watch television or cook together. We celebrated birthdays, Christmas and Easter.”

His claims are widely seen as an attempt to use his own alleged childhood abuse and trauma to justify his later actions. But Adelheid Kastner, the forensic psychiatrist who prepared the report, concluded that Fritzl was cold-blooded and calculating.

“His narcissism combines with the lack of empathy and contributes to the exploitative way of turning others into instruments of satisfying his own needs. There is also a noticeable ability or tendency to ‘modify’ reality according to his own wishes,” Dr Kastner concluded.

On the basis of Dr Kastner’s report, prosecutors will demand that Fritzl be tried and sentenced as clinically sane but then confined in an institution for the criminally insane for the rest of his life. He faces charges of manslaughter in connection with the baby that died, as well as rape, coercion, incarceration and incest.

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