Fritzl daughter takes children back to the incest dungeon for their first visit since release

Incest monster Josef Fritzl's daughter Elisabeth has secretly taken her three children to the cellar dungeon where her father imprisoned them, it emerged today.

The family visited the house of horror with police gathering evidence for Fritzl's trial next month.

It is the first time that Elisabeth and her three dungeon children - Felix, five, Kerstin, 19, and Stefan, 18 - have returned to their prison since they were rescued in April.

It is understood police wanted them to show them exactly where and how they lived in their underground jail, claimed Austrian newspaper Kurier

Elisabeth spent 25 years imprisoned in the cellar of the family home in Amstetten where she was raped repeatedly by evil Fritzl.

Three of her six surviving children were taken from her to live upstairs wth Fritzl and his wife Rosmarie while the others remained prisoners with their mother.

One baby died soon after birth and was thrown into the cellar furnace by Fritzl.

Now Fritzl, 72, is planning to sell the house he turned into a sex-slave dungeon.

The town's mayor Herbert Katzengruber has confirmed that the house - which has become a shrine for sick tourists - will be sold soon after Fritzl's trial.

Grateful Elisabeth and her children have created a special poster for police as a thank you for protecting them since their rescue.

The red poster - with a centipede with the names of the family on it and a butterfly made of foam rubber - was given to police with traditional gifts of cakes and wine.

"We would like to thank you for your constant sympathy and protection. You stood with us during the first, very hard times and made us feel safe and strong," says a message next to the pictures.

Dungeon: A narrow passageway in the cellar where Elisabeth was held for 25 years

Detectives in charge of the investigation have revealed just how confused Elisabeth's cellar children were by the real world after an entire life underground.

Police chief Karl Gschoepf said their first walks in their hospital grounds were a new world to them.

"A cat, a bird - the children knew it all only from TV," he said.

And he hailed Elisabeth as a model mum.

"She is a extremely strong, settled woman who cares for her children impressively.

The children get on really well with each other - this certainly also came thanks to her efforts," he said.

Police minding the family are constantly turning away well wishers from the Austrian clinic that is now the family's home.

"We had detailed instructions who is allowed to see the family and who is not. We had to send away a lot of people," he explained.

And he talked of the pressure on police handling such a high profile case.

"We had no idea what state the family and the mother would be in and whether they would accept us. We were with them constantly and felt with them. It was a dramatic experience for us as well," he said.

For sale: It has been reported that Josef Fritzl wants to sell his home in Amstetten