The main suspect in the disappearance of British toddler Madeleine McCann had a secret Portugal compound guarded by four dogs which hasn't been searched by police.
It's been more than a year now since European authorities revealed 44-year-old convicted paedophile Christian Brueckner was the prime suspect in the case of McCann, who disappeared from an apartment in Praia da Luz, Portugal in May 2007.
While German authorities believe McCann is dead and say they are "very confident" charges will be brought against Brueckner, who is currently locked up in a German prison on sex crimes, he is yet to be interviewed by police. British investigators continue to treat the case as a missing persons one.
Britain's The Mirror reported on Saturday that Dieter Fehlinger, the father of Brueckner's ex-girlfriend, Nicole, has recently spoken to German authorities.
He told them that the pair had a secret compound owned by Nicole on Portugal's Algarve, where Praia da Luz is located and where Brueckner had been living at the time McCann went missing.
No one has searched the property in connection with the young girl but German prosecutors are now examining the new lead.
The father reportedly said the compound was guarded by four Kangal dogs, which are often used to protect flocks of sheep from wolves, bears and other large predators.
"It's an overgrown property of over 5,000 square metres. It was a secure area, enclosed with fencing and four aggressive Kangal dogs were there day and night," he said.
"The area is completely overgrown, not visible. No one could get in or out, only my daughter and perhaps Brueckner with her."
The Mirror said there is no suggestion Nicole had anything to do with McCann's disappearance.
Brueckner, who has been imprisoned for sexual contact with girls, drug crimes and raping an elderly woman in Praia da Luz, broke his silence earlier this month with a letter saying prosecutors should resign for "persecuting an innocent person".