In a twisted story of incest and abuse, the 73 year old allegedly kept one daughter locked in the cellar of their home for 24 years and fathered 7 children with her, according to police.
As details emerge, reports are that he not only kept that one daughter locked up, but kept 3 other children locked up as well, while the other three were being raised by their grandparents.
These details started emerging after one of the children, the 19 year old known only as Kerstin F, was dropped off at Amstetten hospital last weekend and when doctors made an appeal for the mother to come forward to offer up medical history for the child, the father released the mother to do so.
Josef F allegedly then released the mother and two other children from the cellar, telling his wife Rosemarie that she had chosen to return home, police say.
It was not immediately clear how police were alerted.
The mother, named as Elisabeth F, has been receiving medical and psychological treatment since being discovered.
She appeared "greatly disturbed" psychologically during questioning and agreed to talk only after authorities assured her that she would no longer have to have contact with her father, and that her children would be taken care of, police added.
Other than the 19 year old, there were 6 children, three girls, three boys, ages 5 to 20 and they have all been taken to an unknown safe location.
According to a police spokesperson, Franz Polzer, some of these children, as of their release, were seeing daylight for the first time in their lives.
Statements made by Elisabeth, now 42 years old, show that she alleges she had been raped by her father since she was 11 years old when he lured her into the cellar of the house on August 28, 1984 and drugged and handcuffed her before locking her up.
It was assumed she had disappeared voluntarily when her parents received a letter from her asking them not to search for her.
"Abused continuously during the 24-year-long imprisonment", Elisabeth bore six children while a seventh, one of a set of twins, died soon after birth.
The dead baby was allegedly taken out of the cellar and burnt by Josef.
To top off one unbelievably sick and twisted tale with another one, Josef F's wife, Rosemarie claims she didn't know what was going on.