Prosecutors investigating the disappearance of Madeleine McCann say they are 100 per cent certain she was murdered by a sex offender they already hold in custody.
The German authorities say they have the evidence to charge convicted sex offender Christian Brueckner and hope to conclude their investigation next year.
Hans Christian Wolters, the prosecutor in charge of the case, said: "We're confident we have the man who took and killed her. It is now possible that we could charge. We have that evidence now."
But Wolters said that with Brueckner currently serving seven years in a German jail for raping a pensioner in Praia da Luz, his team are taking their time to build as strong a case as possible against him before bringing charges.
'We have time on our hands'
"It's not just about charging him – we want to charge him with the best body of evidence possible," he said. "When we still have questions, it would be nonsense to charge rather than wait for the answers that could strengthen our position.
"That's why we said we'll investigate as long as there are leads or information for us to pursue. I'm not saying that what we have is insufficient now. But he's in prison, so we don't have this pressure on us. We have time on our hands."
However, Wolters and his team now admit they have no proof Madeleine is dead – despite authorities in Braunschweig, northern Germany, having told her parents Kate and Gerry McCann last year that they had "evidence" she is no longer alive.
Madeleine vanished from her family's holiday flat at the Ocean Club resort in Praia da Luz, Portugal, in 2007, days before her fourth birthday. Kate and Gerry of Rothley, Leics, have said they "hang on to the hope, however small, that we will see Madeleine again".
Wolters now says they have no idea how she died and no DNA or photo evidence linking 44-year-old Brueckner to the alleged murder.
In a direct message to the McCanns he said: "We are confident we have the man who took and killed your daughter."
"All I can do is ask for your patience. I personally think a conclusion will be reached next year. We have no body and no DNA but we have other evidence. Based on the evidence we have, it leads to no other conclusion.
'There is no hope she is alive'
"I can't tell you on which basis we assume she is dead. But for us, there's no other possibility. There is no hope she is alive."
Wolters defended his decision not to show the McCanns the evidence that leads his team to believe Madeleine is dead, saying: "If I did ... it is very possible that they would then no longer have any hope."
Evidence being investigated by German prosecutors include a "confession" alleged to have been made by Brueckner to a friend, along with analysis of telephone communications showing he was at the Ocean Club when Madeleine vanished.
Wolters told the Daily Mirror: "It is circumstantial evidence – we have no scientific evidence. If we had a video of the act or a picture of Madeleine dead with Brueckner on camera, we wouldn't have had to make a public appeal. But we only have circumstantial evidence."
Brueckner was living in a camper van close to Praia da Luz when the three-year-old disappeared. He was just out of jail for petrol theft at the time.
He first crossed the radar of British and German police as a suspect in 2017, but they only went public with it last June. Senior investigators have spoken to potential key witnesses in Germany and Portugal.
'Everything we've found fits in the picture.'
The prosecutor said his team has interviewed a "very big number" of people, but has yet to find the person Brueckner spoke to on the phone around the time Madeleine went missing.
He added: "The case is progressing. We've found no evidence to clear Brueckner of suspicion. Everything we've found fits in the picture. We're perhaps halfway through."
Wolters said it is likely Brueckner - who is now in solitary confinement at Oldenburg prison near Bremen, north-west Germany - will be charged early next year with other alleged offences in Portugal, including the rape of an Irish woman in the Algarve in 2004 and two incidents where he allegedly flashed at youngsters.
He criticised the slow approach of Portuguese authorities in the investigation, accusing them of lacking interest in the case because the victim and prime suspect are both foreigners.
"What takes one week in Germany can take six months in Portugal. I think the interest in the case in Portugal is just not that big, because no Portuguese person is involved. The co-operation with Britain is certainly notably better," he said.
Brueckner denies being involved in Madeleine's disappearance and has refused to speak to police or prosecutors.