HOWZAT

Doctors said today that the teenager, who has been suffering from severe cramp brought on by lack of oxygen, was still in a critical state on life support in an induced coma. No firm prognosis could be made for her.

Asked earlier to compare their condition with that of Natascha Kampusch, the young Austrian kidnapped in 1998 and held in a basement in the Vienna suburbs for eight years, Dr Kepplinger replied: "They are not nearly so articulate as Natascha Kampusch, but have rather been marked by their experience."

Investigators who have been painstakingly searching the 60 square metre (645 sq ft) cellar beneath Mr Fritzl's two-storey home, which he built in 1983, said they were now certain he did not build any other basement dungeons.

In addition to his electrical engineering business, Mr Fritzl also dabbled in property management. He is known to have owned at least one other house in Amstetten, where he spent weekends with his wife and the three adopted children.

Mr Fritzl had planned to tear down the house and erect a block of flats and offices with an underground garage, but his neighbours had taken legal action to prevent the project.

Authorities have been asking how events in the main family house, in a busy street in the small industrial town of Amstetten, 130 km (80 miles) west of Vienna, passed unnoticed for so long.

Mr Fritzl kept his daughter and three of her children in a complex which was, in some places, no more than 1.7 metres (5 ft 6 in) high and contained a rubber-padded cell. Photographs of the cellar show a narrow passageway leading into other rooms that included a cooking area, with children’s drawings on the walls, a sleeping area and a small bathroom with a shower.

He had hidden the entrance to the cell behind shelves and only he knew the electronic code for the concrete door. Police are trying to work out whether it would have been possible for Mr Fritzl to build the dungeon by himself - especially whether he could have put the heavy door into place.

Police say that Mr Fritzl’s wife did not know what happened to her daughter when she disappeared in 1984 and was told that she had joined a sect, coming home only to leave three of the children on the doorstep.

Asked again today whether Rosemarie Fritzl was a suspect, Colonel Polzer replied: "It defies logical thinking to believe that a woman who had seven children with her husband would make it possible for him to have another relationship and father another seven children."

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