Prosecutors insist they have substantial evidence that Madeleine McCann was killed by their German suspect but sharing it would compromise their investigations.
Lead investigator Hans Christian Wolters told the BBC he is “very confident” on eventually charging jailed sex offender Christian Brueckner over the British girl’s death.
"If you knew the evidence we had you would come to the same conclusion as I do,” he said.
“What we have so far doesn't allow any other conclusion at all.”
Wolters said it was “tactical considerations” as to why prosecutors were keeping their cards close to their chests.
“I can't give you details because we don't want the accused to know what we have on him.”
In June, the 43-year-old was named as the prime suspect in the disappearance of the then three-year-old Madeleine, who vanished from her holiday apartment in the Portuguese resort of Praia da Luz in 2007.
Weeks later it emerged investigators discovered hard drives and USB sticks hidden in a plastic bag at a secret lair of Brueckner’s in the German village of Neuwegersleben. Police reportedly found 8,000 digital items including pictures and videos which allegedly document some of his alleged crimes.
Also on the property, Brueckner’s American campervan was allegedly discovered with the swimsuits of little girls inside.
Wolters revealed at the time a mobile phone number registered in Brueckner’s name connected to the mast of the Ocean Club where Madeleine was staying on the night of her disappearance.
Brueckner lived on and off in Portugal for years and spent considerable time in and around the Praia da Luz area.
Brueckner’s rape conviction upheld
In November, Brueckner lost an appeal over his conviction for the 2005 rape of a 72-year-old woman in Portugal. His seven-year sentence was upheld. He is serving a 21-month sentence for drug offences which will end in January.
Brueckner has previous child sex abuse convictions with investigators saying new evidence has emerged to bring further charges over further alleged crimes against children.
British Police continue to treat Madeleine’s case as a missing persons investigation, saying there isn’t enough evidence to rule she has been killed.
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