The 88-year-old Austrian - who was sentenced to life imprisonment in 2009 for crimes including incest, rape, and enslavement - has been in psychiatric detention in a high-security unit at Stein prison.

However, a three-judge regional court in northern Austria, ruled on Thursday that Fritzl, who now has dementia, can be moved to a regular prison as he no longer poses a danger.

The ruling, which paves the way for him to be released from prison into a nursing home, overturned an earlier decision from 2022 when his request to be moved to a regular prison was rejected.

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According to the Austria Press Agency (APA), Fritzl will have to attend regular psychotherapy and undergo psychiatric evaluations during a 10-year probation period at the prison.

The verdict is not yet legally binding and prosecutors have 14 days to submit an appeal, APA reported.

Fritzl's lawyer, Astrid Wagner, told The Associated Press: "In summary, the court has come to the conclusion that it is indeed the case that he is no longer dangerous."

Ms Wagner said she planned to submit such a request next year for Fritzl to be released from prison altogether.

'Monster of Amstetten'

Fritzl became known as the "monster of Amstetten" after the northern Austrian town where he locked up his then 18-year-old daughter in a sound-proofed basement of his house in 1984.

Over the next 24 years, he repeatedly raped her and fathered seven children with her, one of whom died.

He claimed she had run off to join a cult, while Fritzl's wife, who lived on the second floor of the home with the rest of the family, was allegedly unaware of what was going on in the basement, according to Austrian authorities.

Fritzl had already been sexually abusing his daughter since she was 11.

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His crimes were revealed after his daughter re-emerged from the dungeon-like basement chamber in 2008 when one of his children with her became critically ill.

After Fritzl took the child to the hospital, police issued an appeal for the mother of the child to come forward.

Fritzl released his daughter from the cellar and the police were alerted to her reappearance, and she told them she had been held captive for more than two decades.

He was sentenced to life imprisonment in 2009 for incest, rape, coercion, false imprisonment, enslavement, and the negligent homicide of one of his infant sons.

In 2023, Fritzl claimed in an interview that he thought his family would "forgive" him for his crimes and he would be "reunited" with them.

Fritzl's daughter and her children have since taken on new identities.