The prime suspect in the disappearance of Madeleine McCann was not interviewed by police in 2007 because he was not at home when officers knocked on his door, a former lead detective has claimed.
Christian Bruckner was one of 600 people of interest investigated by police in the wake of Madeleine's disappearance, but officers who were dispatched to speak with the convicted paedophile returned with no information and never followed him up.
In a television interview, Goncalo Amaral, the controversial police chief who blamed the McCanns for Madeleine's disappearance, admitted that it was not possible to investigate every potential perpetrator in enough detail.
"I have been told that, yes, they had come knocking on the door, that person [Bruckner] was not at home," he told the Portuguese TV channel TVI. Amaral was taken off the McCann case for a series of crucial mistakes including not securing the crime scene properly, and launching a bungled investigation into Madeleine's parents, which was dropped after eight months.
Defending his force's missed opportunity with Bruckner, Mr Amaral said: "We are doing a survey of people known for theft, namely thefts in apartments. And apparently this man was not on the list of thefts in apartments; he had stolen fuel."
By May 2007, when Madeleine went missing, Bruckner had spent eight months in prison for siphoning 321 litres of diesel out of parked lorries in the nearby town of Portimao. He had one other charge of civil disobedience on his criminal record in Portugal.
But last week it emerged that as he stood trial for the fuel theft, he told a judge that he had historic child sex convictions in Germany from when he was a teenager. This was apparently never passed on to police, so the officers investigating Madeleine's disappearance had no idea that a convicted paedophile had been living a kilometre from her apartment.
Amaral also claimed that Bruckner was being made a "scapegoat", German authorities had doctored photos of his campervan and that the McCanns were liars.
"He's an almost perfect suspect, or scapegoat. All that's missing for him to become the perfect suspect is for him to be dead," said Mr Amaral.
When asked if he thought the German had taken Madeleine he said: "To answer that question it has to be proven first that an abduction took place." He also pointed to his own photo of the VW Westfalia campervan which was covered in stickers and drawings on the side, which he claimed was taken in Portugal.
"I think it's important to ask why the photo put out by the authorities of the van was altered. Would that vehicle have gone unnoticed in Praia da Luz with those markings on it? I don't think so."
It was noted that the van may well have looked different in 2007.
Yesterday, it emerged that Bruckner was also the registered owner of a white Mercedes-Benz 205D van and a grey Opel Ascona when Madeleine went missing. The whereabouts of both vehicles is unknown but neither is thought to have been examined by forensic experts.
Bruckner has now been linked to six vehicles, with only three searched by police. (© Daily Telegraph, London)
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