Smash hit

All seven children were conceived and born in the cellar, police say, but within months of their births they were divided between the dark and the light. As babies aged between nine and 15 months, three of the children were adopted and raised by their grandparents, leading normal lives - attending school and playing in the swimming pool in the gardens of the villa.

The three babies were said to have been discovered on the doorstep of the villa between 1993 and 1997. Each baby was left with a note supposedly written by their missing mother Elisabeth, whom the authorities believed had probably joined an extreme and isolated religious sect.

But in the windowless cellar their three siblings, the two eldest, and the youngest, continued to be kept hidden, allegedly a secret even from their grandmother - never seeing the sun, their only source of light the harsh striplight overhead, and dependant on their mother to teach them to speak, read and write.

A television was their only contact with the outside world, apart from the hatch through which their alleged father/grandfather passed food and clothes.

The sequence of events by which the grim charade was uncovered appears to have begun ten days ago when the oldest child was found unconscious and seriously ill outside the cellar - reports differ to exactly where - with yet another note from Elisabeth asking for her to be given medical help.

She was taken to hospital, where she is said to be in a serious condition. Her doctors issued an urgent appeal for her mother to come forward to supply medical information to help save her life.

Following this appeal Mr F appears to have decided to allow his captives to leave the cellar, telling his wife that the longlost Elisabeth had at last decided to return home with the rest of her children.

He and Elisabeth were held by police on Saturday night at the hospital where the young woman is being treated. Police then found the rest of the children at the villa. It was only last night that detectives gained access to the cellar.

According to Austrian police, Elisabeth F is in a "very bad condition". She was described as "extremely pale", and looking 20 years older than her age, the Austrian broadcaster Orf reported. She is alleged to have given a full statement to police on condition that she did not have to see her father again. Grandmother, mother and children are said to be receiving counselling and medical treatment.

The case has echoes of the Natascha Kampusch affair in which a Viennese schoolgirl was kept in a cellar from the age of 10 for eight years before escaping.

But while Ms Kampusch’s captivity was possible because of the anonymity of the suburbs, Ms F and her children were prisoners in a small, close-knit community. Neighbours talked yesterday of how Mr F’s wife used to take her three grandchildren for walks and how Mr F always gave a cheery greeting.

“This is a shock to all of us,” a neighbour who gave her name only as Maria, 66, said. “I’m good friends with Mrs F. Both she and her husband are lovely people. I’ve seen her take the children to school very often – they are well dressed, polite and very nice. I just saw her the other day and I still cannot believe that this was going on in front of our noses. We always believed that the mother of the children had run away and dumped them on the grandparents. Who would ever think of such a horrible thing?”

Mr and Mrs F have four children besides Elisabeth, all of whom now have families of their own. Mr F is said by police to have presided over all family affairs with an iron hand. But how he managed to keep a secret so horrifying behind an underground door will puzzle psychiatrists and sociologists for years as they decide whether there is such a thing as an “Austrian syndrome”.

As Austrians woke this morning to the realisation that yet another horrific child kidnap case has been taking place in their midst, the news is likely to fuel a furious debate in Austria about how easy it is to slip through the welfare net. “This is one of the most extraordinary cases in Austrian criminal history,” said Colonel Polzer.

Guenther Platter, the Austrian Interior Minister, said: "We are being confronted with an unfathomable crime. Everything that has happened here goes beyond one's imagination."

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