Josef Fritzl looked into the eyes of his daughter and former prisoner yesterday for the first time since she was freed from his Austrian dungeon.

It was not, to put it mildly, a conventional family reunion. Elisabeth, his 43-year-old daughter, stared out from a giant 26 inch television set up in a darkened courtroom and spoke during eleven hours of pre-recorded testimony about a quarter of century of physical and sexual abuse at the hands of Fritzl. Although Ms Fritzl was nowhere near court, shielded from paparazzi with her six children in a psychiatric clinic, her presence dominated the murder, rape, enslavement, imprisonment and incest trial against her father.

"Mr Fritzl watched the recordings with his full attention, I cannot imagine his emotional state," said court spokesman Franz Cutka. The deputy governor of the St Pölten detention centre confirmed yesterday however that Fritzl had been put on suicide alert. The 73-year-old building engineer had seen a psychiatrist on Monday night after hearing the charges against him in courtroom 119 in St Pölten. "He [the psychiatrist] is now standing by in pauses during the court hearings," said Erich Huber-Günsthofer.

Yesterday Fritzl had to hear from the mouth of his daughter, and it cannot have made for a pleasant day for a man who never tolerated back-chat in his family of 12 children. As one commentator put it: "Elisabeth has returned as an avenging angel."

Reporters were banned from the court room, to protect the privacy of Elisabeth, but Fritzl sat in the dock, with the three judges, eight jurors, the state prosecutor and the defence team. As Ms Fritzl recounted her litany of humiliations, the tape was stopped and Fritzl was cross-questioned. The main aim of the proceedings was to address the most serious charge against Fritzl, that of murdering one of the seven babies fathered in the mouldy fetid cellar of his sprawling house in Amstetten.

A doctor specialising in neo-natal medicine presented his analysis of the final hours of Michael, a twin born on April 28 1996. The court wanted to establish whether — as alleged in the indictment — the baby died of an infection which led to respiratory distress.

According to the indictment, read in court on Monday, Fritzl had dinner in the cellar that night with the two older children as Elisabeth went into labour.

Michael, the first born twin, was in trouble. "The accused could see that Michael's situation was getting worse," says the charge sheet, "Fritzl was fully aware of this. Instead of calling for emergency medical care for the newborn and securing help for the baby, Fritzl simply told Elisabeth 'what will be, will be'".

The baby died two days later. Fritzl denies being in the cellar at the time of death, and considers himself not guilty of "murder by neglect". Elisabeth's version — which forms the basis of the indictment — was clearly essential.

Ms Fritzl recorded her testimony last summer, three months after her release from the cellar of the family home. The memories of her ordeal were still fresh and state prosecutor, Christiane Burkheiser, remembers the occasion — the taping was held over several days, in the presence of psychiatrists and Fritzl's defence lawyer Rudolf Mayer — as being particularly gruelling. "This was much more emotionally difficult than questioning Mr Fritzl," said the 33-year-old state prosecutor in an interview.

The taped testimonial provided the basic material for the indictment which describes a history of sexual abuse from the age of 11. As a teenager she ran away from home to escape the alleged beatings. The court heard that she later confided in her brother Harald who is four years older. His pre-recorded testimonial was also viewed in court yesterday.

Ms Fritzl was repeatedly raped by her father and, according to the indictment, suffered from internal injuries as the result of his assaults. Fritzl has confessed to the charges of rape, coercion, deprivation of liberty and incest. He denies not only murder but the also the charge of enslavement.

The taped testimony has been introduced to spare Elisabeth the need to be in the same room as her father — she vows that she never wants to see him again — but it has made for a strange trial.

The court is racing through proceedings. Almost all of the taped testimony of Elisabeth and Harald were viewed yesterday, the medical expert was heard and Fritzl cross-questioned. Tomorros, different expert testimonials, including that of Dr Kastner, will be read out and the judges will then go into closed session to frame their questions for the jury.

Those questions will be posed on Thursday morning — the jurors will have to answer "yes" or "no", rather like ticking the boxes of a questionnaire. By Thursday afternoon the judges will probably be ready for sentencing.

Austria's trial of the century, in other words, will have lasted only four days from beginning to end.

The motivation of Fritzl will be crucial in the judge's decision as to whether — if found guilty — he should be sent to jail or to a closed high security psychiatric institute.

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