London, Oct 30 : Austrian incest fiend Josef Fritzl has confessed that he locked up his own mother in a bricked-up room till the time she died in revenge for allegedly abusing him.

The room was in the same house where Josef later incarcerated his daughter and grandchildren.

He made the astonishing revelations to a psychologist preparing a report for his trial for imprisoning and sexually abusing his daughter Elisabeth.

His mother could have been locked away for more than 20 years in the house in Amstetten, according to an Austrian tabloid.

"I locked her 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," the Telegraph quoted Fritzl, as saying in the leaked psychologist''s report.

Fritzl told neighbours that his mother died around the time he took ownership of her home in 1959, but the Oesterreich newspaper claims she did not die until 1980, suggesting that she could have spent 21 years in the locked bedroom.

Fritzl''s friends have expressed doubt that he could have kept her hidden in the house for so long.

The 73-year-old told the psychologist that he wanted to punish his mother for his loveless, 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," he said.

"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,” he added.

Asked if this had given him the idea for locking up Elisabeth, he said: "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."

Fritzl also told the psychologist that he was "born to be a rapist".

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

Fritzl locked up daughter Elisabeth for 24 years near Amstetten, Austria. He raped her and forced to have his seven children.

Fritzl''s trial is due to begin in February. He has confessed to the crime, but the charges have yet to be finalised. (ANI)