AMSTETTEN – A 73-year-old Austrian admitted on Monday to having fathered seven children with his daughter whom he kept imprisoned in a dungeon (see photo of house) for 24 years, while officials rejected any responsibility for the tragedy.

Josef Fritzl, a retired electrical engineer from Amstetten in eastern Austria, confessed to having locked his daughter, Elisabeth, 42, in the basement in August 1984, and to having abused and raped her repeatedly, authorities said at a press conference.

"This crime is more or less solved," provincial police chief Franz Pruchner said. "This crime is unique in the criminal history of Austria. It is beyond all dimensions I know of."

Josef had confessed to the crimes after his initial refusal to cooperate with the authorities, but tried to mitigate the details.

He showed next to no regrets, authorities said.

During her captivity, Elisabeth gave birth to seven children, results of continued sexual abuse by her father.

One infant died shortly after his birth. The father disposed of the body by burning it in the house’s central-heating boiler, he told police.

After Josef’s arrest on Sunday, police were investigating the dungeon hidden in the basement of his house where Elisabeth and three of her six surviving children had been imprisoned.

Three of the children, aged between 5 and 19, were imprisoned with her for all of their lives.

The other three lived with their "grandparents" and attended local schools.

Josef had told authorities that his daughter, whom he reported missing after her "disappearance," had deposited the infants on his doorstep over the course of several years.

Local authorities stressed that they were not to blame for the tragedy, adding that Josef had led a perfect double life.

"He deceived everyone," Pruchner said.

His wife, Rosemarie, 69, and other family members did not notice anything, Pruchner said.

Police arrested Josef on Saturday after he was persuaded by Elisabeth to accompany her to the local hospital, where her oldest daughter, Kerstin, was in a very severe condition.

Kerstin, 19, one of the three children incarcerated with her mother, is believed to suffer from a rare disease.

Her mother persuaded Josef to get the girl to hospital, which triggered the search for the mother last week.

"A shred of humanity remained," Pruchner said.

Authorities expect the results of DNA testing aimed at verifying the suspicions of incest later on Monday, but said after the confession, this was more of a formality.

"The man confessed to having fathered the children and said that no-one else had access," Pruchner said.

Elisabeth and five of her children are being looked after by doctors and therapists.

Five-year old Felix was in good shape, district head Hans-Heinz Lenze said.

He added that he was told by doctors that all of them were in relatively good physical shape, but said the family was concerned over the media interest.

[dpa / ANP / Expatica]