Josef Fritzl pleaded guilty to incest, rape and sequestration on Monday for locking his daughter in a cellar for 24 years, but denied charges of murder and enslavement.

Flanked by several police officers, the defiant 73-year-old Austrian entered the courtroom in St. Poelten clad in a mismatched grey suit. “Authorities fear Josef Fritzel could try killing himself,” says FRANCE 24’s Philomé Robert, reporting from St. Poelten, near Vienna.

Fritzl is accused of locking up and raping his daughter, Elisabeth, for 24 years in a cellar of his home, fathering her seven children. He is being charged with murder for the death of one of the babies in 1996.

If convicted of murder, Fritzl could receive a life sentence or up to 15 years in prison. Under Austrian law, sentences are not cumulative and only the highest one is handed out if a defendant is found guilty on several counts.

On Monday, only two testimonies were heard in court: that of Fritzl, the accused, and part of a pre-recorded video testimony by his daughter, Elisabeth.

Follow Angela Yeoh's Tweets from the Josef Fritzl trial. If the box is empty, click here to follow angela_f24 on the Twitter site

At a press conference convened at the end of the first day of proceedings, court spokesman Franz Cutka said the trial would resume on Tuesday at 9 am local time. Tuesday’s proceedings will be closed to the public and the media to protect the victims' identities.

When asked why a crime of such long duration could have so few witnesses, Cutka said, “There have been no further requests for witnesses or testimonies. No one has decided to testify, they have refused,” he added.

Speaking to the press on Monday, Cutka said the verdict could come as early as Thursday. The jurors will then decide the sentence in cooperation with the three judges.

The “monster trial”

The trial - which has been dubbed “the Monster Trial” by the Austrian press – has attracted national and international attention. But during his opening statements on Monday, Fritzl’s attorney Rudolf Meyer argued that his client was “not a monster.”

At Monday’s press conference, Hubert-Guensthofer, deputy director of the prison where Fritzl is being held, described the behaviour of his prisoner. "In prison he behaved quite normally,” he said. “He’s not unusual. If he were standing here, you wouldn’t notice him; he behaves according to the rules. He is very polite.”

Reporting from St. Poelten, FRANCE 24’s Robert said the case has shocked the nation and raised a number of issues. “The main question is how the whole affair passed unnoticed,” said Robert. “For example, in 1984 when Fritzl said his daughter had run away to join a sect, no investigation was carried out.”

Fritzl found guilty, given life imprisonment (19/3) The Monster business (17/3) 'Fritzl schnitzel' - not funny (17/3) Hometown: 'Leave us alone' (15/3) An ordinary neighbourhood... (13/3) Observers: "Fritzl of Mumbai" (19/3)

Elisabeth was imprisoned in the family home’s basement at the age of 18. Her father made her write letters pretending she'd run away to join a sect.

Of the seven children, one died shortly after birth. Fritzl took three others upstairs, convincing his wife Rosemarie to take them in. Three stayed in the cellar with their mother until they were finally released last April.