Serial killer Levi Bellfield is alleged to have confessed to one of the UK's most notorious murder cases.
Lin Russell, 45, and daughter Megan, six, were killed months after moving to Kent from north Wales. Josie, nine, survived despite horrific injuries.
Michael Stone was found guilty in 2001 largely on the strength of a disputed cell confession.
When contacted by BBC Wales Bellfield denied being responsible for the murders and making any confession.
At a press conference on Wednesday by Stone's legal team, solicitor Paul Bacon said: "We have seen evidence of a full confession by Levi Bellfield that he has admitted the Russell murders and in the confession Bellfield describes how he came across Lin Russell and her two children.
"How he attacked them with a hammer and he explains his motivation for the killing. The confession is detailed and has a number of facts that are not in the public domain.
"We now have an independent witness who has seen Levi Bellfield close to the scene of the murders at about the time they were committed and importantly we have identified forensic material from the scene of the murders which corroborates the confession made by Levi Bellfield.
"The Russell murders by Levi Bellfield fits perfectly with his modus operandi. He is a man known to attack and murder women. His weapon of choice is a hammer.
"This material including the detailed confession is before the Criminal Cases Review Commission. We are of the view that this evidence must, as a matter of urgency be brought before the Court of Appeal."
Stone's legal team are calling for an independent police force to investigate the new evidence.
They say all conversations had been written up contemporaneously and immediately reported to a solicitor by the prisoner who Bellfield allegedly confessed to.
It is claimed Bellfield - currently serving two whole life terms - said he was worried about DNA advances saying "my life in jail would be over if they could prove it was me" and that it would "tear his mother in two".
Known as the 'Bus Stop Killer', he randomly launched a so-called 'blitz attack' from behind, striking his victims repeatedly on the head with a hammer.
In 2011 the nightclub bouncer, drug dealer, and wheel-clamping contractor was convicted of abducting and murdering 13-year-old Milly Dowler as she walked home from school in Surrey in 2002.
By then he had already been convicted of three other attacks in south west London - murdering 19-year-old Marsha McDonnell in 2003, Amelie Delagrange, 22, in 2004 and in the same year attempting to kill 18-year-old Kate Sheedy, by running her over. She survived her injuries.
It is widely believed by detectives that Bellfield is responsible for numerous crimes dating back to the 1980s.
And this is not the first time his name has been linked with the Russell murders.
Even though the attack happened over 20 years ago it remains one of the UK's most notorious cases.
The mother and two daughters were attacked just before 16:30 BST on 9 July 1996, as they walked with the family dog home from school in Chillenden, near Dover.
Half way along a country lane, they were accosted by a man, tied up, made to sit in a copse, blindfolded and bludgeoned with a claw hammer, one by one.
When they were found eight hours later; it was thought all were dead.
Josie was found to have a faint pulse. Remarkably, she survived. She lives and works as an artist in north Wales, having returned to Gwynedd with her father soon after the attack.
A year after the murders a tip off to Crimewatch from a psychologist who worked at a local psychiatric assessment centre, led to the arrest of 36-year-old Michael Stone from Gillingham.
In October 1998, Stone, a heroin addict with a criminal history, was convicted.
In the absence of any forensic evidence, the jury believed the main thrust of the prosecution's case - three prison inmates who claimed Stone had confessed.
One of the inmates admitted soon after the trial ended that they had lied and another was discredited.
Stone's legal team challenged his conviction. A retrial was ordered.
But one of the inmates, Damien Daley, then aged 26, held firm to his claim that Stone had confessed to him in grisly detail.
The judge's summing up to the jury was unequivocal: "The case stands or falls on the alleged confession of Damian Daley."
In late 2001, Stone was once again found guilty and given three life sentences.
As the judge addressed him, Stone cried out: "It wasn't me your Honour, I didn't do it!"
Since then Stone has failed in two appeal bids.
"Given what we know about the lack of evidence… presented to the jury in the actual trial," Stone's barrister Mark McDonald QC says, "this confession is so profound, significant, that it goes to the heart of the conviction of Michael Stone. It's unsafe."
When asked to respond to the possibility of new allegations in this case, Kent Police said that Stone's protests of innocence had been thoroughly tested by the judicial system.
Ever since Bellfield's conviction for the murder of Milly Dowler, Stone's legal team have claimed Bellfield may have been responsible for the Russell murders.
Meanwhile, Bellfield has been contacted by BBC Wales Investigates and denies both the murders and the confession.
He claims he has three letters from Stone and has complained about his "persistent attempts" to get him to take responsibility. He also alleges Stone has offered to give him a share of any compensation money he might get.
Lie detector test
Stone vehemently denies this.
Bellfield added that he had challenged Stone to a lie detector test. Stone has spoken about his reluctance to do this claiming he had been advised that his history of psychiatric problems and drug addiction could impact its accuracy.
Recently there has been a war of words between the two convicted killers from behind bars at Durham's Frankland prison where they are both being held, which has been reported in newspapers.
A BBC Two investigation of the Russell murders entitled The Chillenden Murders was broadcast in June this year. A panel of experts was given access to all case files to re-examine the evidence.
It is this programme which is claimed to have prompted Bellfield's alleged confession.
The panel concluded that despite advancements in DNA there was still no forensic link to Stone and it was likely another man was at the scene.