The Austrian man who kept his daughter as his personal sex slave for 24 years in a home-made dungeon under his house has complained about "completely one-sided" press coverage of his case.

As prosecutors prepared to interview him for the first time, Josef Fritzl, 73, said through his lawyer that he could easily have killed his daughter and the children she bore him.

"I am not a monster," Mr Fritzl said in a statement reported by the German tabloid Bild.

Mr Fritzl has admitted imprisoning his daughter Elisabeth, now 42, in a cellar he built himself and fathering seven children with her.

Commentary: a society that nurtures secrets

What society would accept the probability of three children being left on the doorstep of Josef F and grant him adoption?

Multimedia

• Pictures: house of horror

Background

• Why are child abuse scandals happening in Austria?

• Analysis: damage caused may never be healed

• Austria: sedate town is stunned by news

• Police search other Fritzl properties in Austria

Related Links

• Why he did it: Joseph Fritzl's statement

• Scared prostitutes 'shunned Fritzl'

• Fritzl 'began building cellar in 1978'

Multimedia

• Video: Fritzl lawyer says family is coping well

Three of his children, including a 19-year-old woman, Kerstin, who is critically ill in hospital, lived all their lives in the dungeon until their release ten days ago. Three others lived upstairs with Mr Fritzl and his wife Rosemarie. One child died as an infant.

But Mr Fritzl displayed no sign of remorse in the statement released via his lawyer, Rudolf Mayer, a criminal defence specialist from Vienna, complaining only about the "unfair" treatment accorded him by the press.

He said: “Kerstin would not be alive today if it wasn’t for me. I have made sure that she gets to a hospital.

“I could have killed all of them, and nothing would have ever been known about it. No-one would have ever found about it.”

Mr Fritzl is currently on remand in prison and will appear in court for a closed hearing on Friday.

Mr Mayer said that his client was now a “broken man,” and he would try to have him declared mentally unfit to stand trial. “My client doesn’t belong in a prison; he belongs in a psychiatric ward," he said.

But police and prison authorities claim that Mr Fritzl appears “normal” and “composed”. He is sharing a cell with a 36-year-old violent offender and has been described as a “quiet inmate” who is closely following the news coverage of his case in the media.

He has not been using his right to a one-hour-walk in the prison courtyard, allegedly for fears that other prisoners could lynch him.

Mr Mayer said that he himself had received death threats from Austria and abroad, including Britain.

Reinhard Haller, one of Austria’s leading forensic psychiatrists who prepares expert opinions on serious offenders for local courts, rejected the claims that Mr Frizl was mentally incompetent and therefore not responsible for his actions.

Dr Haller said: “His main motivation was the exercise of power. It is not a sign of mental illness, but rather of an extreme personality disorder.”

Meanwhile, the Fritzl case has reached the Austrian parliament, where MPs will debate today on whether to introduce lengthier prison sentences for sex offenders and allow various government agencies – such as social services – access to their criminal records.

The move comes after it was revealed that Mr Fritzl had previous convictions for rape and attempted rape , and had faced charges of arson, but was nevertheless awarded custody of three children born out of the incestuous relationship with his daughter whom he claimed she had abandoned. According to Austrian laws files on sex offences are being removed from the records after ten to 15 years.

Maria Berger, the Austrian Justice Minister, has admitted that authorities have mishandled the Fritzl case for the first time and said that police and social services had acted “somewhat gullibly”. She said that the disappearance of Elisabeth in 1984, when her father kidnapped her but told authorities she had run away to join a religious cult, was “not sufficiently investigated”.

“Today, we would surely investigate a case like this much more thoroughly,” Mrs Berger said.

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