GERMAN cops have been warned that their case against the prime suspect in Madeleine McCann’s disappearance could collapse due to their “Bulls***” witness.
The investigators’ over-reliance on “tarnished” evidence from the key witness could destroy their fight for justice, insider sources claim.
A damning statement by Helge B — an old friend of Christian B, 45, the prime suspect in the case — has become a cornerstone of the German-led police investigation.
However, a source close to the Portuguese Police told The Sun that German cops are “bluffing” in saying the evidence from key witness Helge B, 48, is “only one part of the puzzle.”
Instead, they claimed that the case has come to rest too heavily on his evidence, which is “so tarnished” that it will damage the probe.
The source argued that Helge B should be asked to take a lie-detector test to see if his claims against Christian B are actually true.
They added: “This would solve once and for all if his evidence can be believed.”
Last week, the police case appeared close to collapse as sources close to the investigation revealed that Helge B was “wobbling” and threatening to stop helping.
A German source told The Sun: “Word is that Helge B is about to withdraw his evidence.
“He was paid a huge sum to repeat his statement in a German newspaper and now he’s pulling the plug.
“It just goes to show you what type of people you are dealing with — and their credibility as witnesses.”
It comes as other sources told The Sun that German officers were warned long ago about Helge B’s “flakiness” and even referred to the star witness as “Helge Bulls****er”.
He said: “Helge B is someone the Portuguese officers have known about for a long, long time. But he was discounted as a credible witness ages ago.
“He was always seen as a Walter Mitty character who would talk ‘BS’ all the time hence the nickname.
“They warned the Germans he was a bit of a fantasist and that he was ‘flaky’ and how he’d say what you wanted to hear. But, for some reason the German detectives latched on to him.
“They’ve pinned pretty much their entire case on his evidence, despite being warned he wasn’t to be trusted. Now, with him looking to back out, their credibility has been totally shot to bits.”
In a tell-all interview in June, Helge B also alleged that he tipped off Scotland Yard about his former friend in 2009, but said: “I was never called back.”
The search to find Madeleine’s killer has gone on for 16 years now and it’s feared that Helge B’s threats for withdraw evidence could unravel the long fight for justice.
It could be the final blow in the stalling bid to bring Christian B to court for the suspected abduction and murder of three-year-old Madeleine in Portugal in 2007.
The move would be yet another cruel setback for the McCann parents Gerry and Kate, both 55, of Rothley, Leicester.
German Helge B was a criminal pal of drifter Christian B when they lived in the Algarve around the time of Madeleine’s disappearance from her holiday apartment in Praia da Luz.
He told cops he was chilled by Christian B’s alleged dark confession when the pair met at a music festival in Spain a short time after the toddler vanished.
As the pair discussed the case over beers, Christian B was said to have coolly confided: “She didn’t scream.”
The convicted rapist and child sex attacker clearly implied he had taken Madeleine, Helge B told cops.
McCann probe prosecutor Hans Christian Wolters said he was unaware of Helge B’s suspected change of heart — but insisted his statement would still carry weight.
He said: “Anyone who has said something must be measured by it. Witnesses are subject to the duty of truth — they have to testify. You can’t just choose something like that.”
Christian B is currently in jail in Germany for the 2005 rape of a 72-year-old American woman also in Praia da Luz.
Detectives claim to have “concrete evidence” that Madeleine is dead but have yet to produce further material which could lead to a charge.