"I bricked the window so she never saw daylight"

Josef Fritzl admitted locking up his mother until her death in the same house as he later imprisoned his daughter and the seven children he fathered with her, London's Daily Telegraph reports.

"I locked (my mother) up in a room at the top of the house, I then bricked in the window so that she never again saw the light of day." Josef Fritzl said in the leaked psychologist's report.

According to neighbours, fritzl told them about his mother's death in around 1959, when he took ownership of the house. However an Austrian newspaper claims that Fritzl mother did not die until 1980, suggesting that she was locked up for 21 years.

It emerged in April that Fritzl has been keeping his daughter, Elisabeth, locked up in the purpose built room and sexually abusing her for the past 24 years. This was the same room where he kept his mother locked.

When inquired, he said that he wanted to punish his mother for his loveless and brutal childhood. "She used to beat me, hit me until I was lying in a pool of blood on the floor. It left me feeling totally humiliated and weak," the 73-year-old told the psychologist. "My mother was a servant and she used to work hard all her life, I never had a kiss from her, I was never cuddled although I wanted it - I wanted that she would be good to me. But the only thing she ever did with me was to go to the church".

When asked if all of that has anything to do with what he has done to his daughter? "To be honest I just didn't think about it, about her being my daughter, I saw her as my wife and as my partner" he replied.

He said that "He was born to be a rapist". These revelations are contained in a 130-page report compiled by Dr. Adelheid Kastner of Wagner-Jauregg mental asylum in Linz.

Dr Kastner advised that Fritzl was not insane, but he was a danger to public and should never be released from prison.

Charges against Fritzl are yet to be finalised.