Just weeks ago it was believed the most famous serial killer in history had at long last been identified.
Jack the Ripper, who murdered at least five women in London’s East End in 1888, was finally unmasked as a Polish immigrant barber named Aaron Kominski.
Businessman and amateur sleuth Russell Edwards announced the findings after hiring Dr Jari Louhelainen, an expert in the forensic investigation of historic crime scenes.
A contemporary illustration of the discovery of Catherine Eddowes' body
Dr Louhelainen’s analysis of a shawl owned by one of the Ripper’s victims, Catherine Eddowes, reportedly revealed Kominski’s DNA to be present – after comparisons with swabs taken from one of his British descendants.
But rather than being the final piece of the grisly jigsaw, it is now alleged Dr Louhelainen made an “error of nomenclature”, the Independent writes.
It reports Dr Louhelainen “appears to have made a basic error” in his calculations by placing a decimal point in the wrong place, when using a DNA database to calculate the chances of a genetic match.
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This error is alleged to have led him to mistakenly assume the DNA sequence he identified was more rare than it really was.
The newspaper cites experts in the field, adding: “If true, it would mean his calculations were wrong and that virtually anyone could have left the DNA that he insisted came from the Ripper’s victim.”
Edwards, whose book on his findings which was serialised in the Mail on Sunday last month, wrote: “I was overwhelmed. Seven years after I bought the shawl, we had nailed Aaron Kosminski.
"Kosminski was not a member of the Royal Family, or an eminent surgeon or politician. Serial killers rarely are."
A fanciful engraving showing 'Jack The Ripper' being caught red-handed
"Instead, he was a pathetic creature, a lunatic who achieved sexual satisfaction from slashing women to death in the most brutal manner. He died in Leavesden Asylum from gangrene at the age of 53, weighing just 7 stone.”
A spokesman for publishers Sidgwick & Jackson said they were investigating the reports but that “the author stands by his conclusions.”
The mystery surrounding the identity of the killer has seen suspects range from the painter Walter Sickert, to Alice in Wonderland author Lewis Carroll, to the wife of an eminent Victorian surgeon.
Meanwhile some say the murderer was a female Salvation Army worker, and others claim he didn't exist at all...
WARNING: The gallery below contains some graphic content