An eerie silence descended upon this sleepy town yesterday as its 23,000 inhabitants learnt from the television news of the horrors said to have been perpetrated in their midst for almost three decades.

The only sign of life was at Ybbs Street, where a legion of international TV crews and news organisations besieged an inconspicuous blue three-storey house, the home of a retired middle-class couple well known and well respected in the tight-knit community.

As a police spokesman held an impromptu press conference in front of the house, neighbours listened with disbelief to the allegations of how a retired electrical engineer, kept his daughter EF, 42, imprisoned in a subterranean dungeon. He adopted three of the children he is alleged to have fathered with her. They went to school and had a normal life in the apartment upstairs. The other three were allegedly imprisoned two storeys below and, until this weekend, had never seen daylight.

The only window on the outside world was a TV set that police said was the only concession retired electrical engineer made for his secret family.

“This is a shock to all of us,” a neighbour who gave her name only as Maria, 66, said. “I’m good friends with them. 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?”

But surely someone had questioned the whereabouts of a woman who had gone missing since 1984 and had three children growing up with her parents?

“There are no records of EF. She has not had any dealings with the authorities since her disappearance in 1984 and there are no photos or files on her,” a police spokesman said.

The neighbour, Maria, despite claiming to be friends with the family, admitted that she could not remember ever knowing their first names, although she had known them for decades.

The father worked as an engineer for the construction company Zehnter. As well as EF he had four children, all of whom now have families of their own.

The police said that the dungeon in the house was taboo for the rest of the family, including his wife, who claimed to have known nothing about her daughter’s fate.

The father is said by police to have presided over all family affairs with an iron hand. But just how he managed to keep a secret so horrifying behind an underground iron door will puzzle psychiatrists and sociologists for years to come as they decide whether there is such a thing as an “Austrian syndrome”.

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