Spy Death Mystery 'May Never Be Solved'

A coroner has said an MI6 codebreaker whose body was found in a sports bag at his London home in the summer of 2010 was probably "unlawfully killed" - but there is not enough evidence to prove it.

Despite seven days of inquest evidence and a 21-month police inquiry, Dr Fiona Wilcox said it was "unlikely" the circumstances surrounding Gareth Williams' death "will ever be satisfactorily explained".

The maths prodigy's body was found curled up in a padlocked holdall in the bath of his flat in Pimlico, central London, in August 2010.

Dr Wilcox said she was sure a third party had locked Mr Williams inside the bag.

"The cause of his death was unnatural and likely to have been criminally mediated," she said in her two-hour narrative verdict at Westminster Coroner's Court.

"I am therefore satisfied that on the balance of probabilities that Gareth was killed unlawfully."

But Dr Wilcox did not record a verdict of unlawful killing because she said there was insufficient evidence to categorically prove his life was taken by someone.

The coroner also said it remained a "legitimate line of inquiry" that the secret services were involved in the spy's death because he had socialised with so few people.

But she stressed "there was no evidence to support that he died at the hands of" spies.

Mr Williams' family criticised his employers for their response to his death, saying "our grief was exacerbated" by it.

The head of MI6 apologised "unreservedly" to the family for the way the police inquiry was hampered by his colleagues.

Dr Wilcox said it was "highly unlikely" that Mr Williams got inside the red holdall alone, and he would have been unlikely to have invited a third party who was not a family member into his home.

She said if someone else was there without having been invited "that raises the possibility of an illegitimate purpose on the third party's part".

"Gareth may have worked out a technique how to get into the bag and lock it from inside but I find it extremely unlikely that he did so," she added.

Dr Wilcox ruled out Mr Williams' interest in bondage and drag queens in having any bearing on his death as she questioned leaks about his private life to the media, saying: "I wonder if this was an attempt by some third party to manipulate the evidence."

The coroner appeared to rule out that Mr Williams died as a result of some kind of "auto-erotic activity".

"I find on the balance of probabilities that, if he had got into the bag and locked himself in, he would have taken a knife in with him," she said, adding: "He was a risk assessor."

The inquest had heard that £20,000 of women's clothes and shoes were found in Mr Williams' flat, but Dr Wilcox said there was no evidence to suggest he was a transvestite "or interested in any such thing".

Dr Wilcox criticised MI6 for failing to raise the alarm about Mr Williams' disappearance until a week after he was last seen.

Breakdowns in communication by her own coroner's office in ordering a second post-mortem, a DNA mix-up by forensics and the late submission of evidence by MI6 to police were also singled out for blame.

After the verdict, Sir John Sawers, chief of the Secret Intelligence Service (SIS), apologised to Mr Williams' family for MI6's failings to report the codebreaker's disappearance for a week.

The MI6 chief said "lessons have been learned, in particular the responsibility of all staff to report unaccounted staff absences".

But Mr Williams' family hit out at his employers for their response to his death, saying in a statement read out by their lawyer that they were "extremely disappointed" at the secret services' "reluctance and failure" to make relevant information available to the inquest.

They also attacked the "total inadequacies" of the inquiry by Metropolitan Police counter-terror branch SO15 into MI6, and called Scotland Yard's chief to look into how the ongoing investigation would proceed in light of this.

The family went on to describe the highflying codebreaker as a "special and adored son and brother" who they missed "every single day".

"(We) cannot describe the depth of the sorrow his absence leaves in our lives. We love you, Gareth, and will treasure your memory eternally," they said.

Pathologists said when Mr Williams' body was eventually discovered it was badly decomposed and three post-mortem examinations could not establish the cause of death.

Sky News' reporter Mark Stone, at the inquest, said: "The crux of this inquest has been to establish how Mr Williams got into the bag and locked it from the outside, if indeed it was he who put himself into the bag.

"With this particular case it's very difficult. No one knows exactly how he died, whether he was alive or dead when he got into the bag, where did he die and whether anyone else was involved.

"The police have said all along that they believe a third party was involved although they have no strong evidence for that.

"The coroner has recorded a narrative verdict because of the evidence and she can't come to any other conclusion."