27/12/2012 05:16 GMT | Updated 27/12/2012 09:21 GMT

Gareth Williams Death: MI6 Spy 'Climbed Into Bag Himself'

An MI6 spy who was found naked inside a locked holdall may have crawled inside the bag himself, a source close to the investigation has told the Daily Telegraph.

A review was conducted into the case by the Met Police after the coroner Dr Fiona Wilcox said that 31-year-old codebreaker Gareth Williams was "probably" killed, adding that she was sure someone else locked him in the bag.

Secret service involvement in his death was a "legitimate" line of inquiry she said. DNA samples were taken from up to 50 of his colleagues, the Daily Mail reported in May.

However a source close to the inquiry has now told the Daily Telegraph that despite their two year investigation into the mystery they now have "every reason to believe that Gareth may have climbed into the bag himself and been unable to get out.”

The source added: “They have been unable to find any trace of anyone who should not have been in the flat."

The Met Police has said all lines of inquiry continue to be pursued.

The investigation into Williams death since the spy was discovered in August 2010 has taken a number of twists and turns, all centering around whether the 31-year-old could have locked himself in the red North Face holdall and why he would attempt such a feat.

Screengrab from a video reconstruction showing a yoga specialist trying to lock himself in a sports holdall unaided

Details of his private life were leaked to the press, suggesting he had an interest in bondage and drag queens. The pathologist who carried out a post mortem on Williams, told BBC Radio 4's Today programme in May the death could fit "neartly" with other deaths from sexual asphyxiation.

"From my point of view, as I look across the deaths associated with sexual asphyxiation, this is one that fits quite neatly into that product, bizarre though it is."

Expensive women's clothes, shoes and wigs were found inside Williams' Pimlico flat, along with a video that showed him gyrating in nothing but a pair of black boots.

The inquest also heard that Mr Williams, a codebreaker for GCHQ who was on secondment to MI6, had been found in his boxer shorts and tied to his bed by his landlord and landlady in Cheltenham a few years earlier.

Both his family and coroner Dr Wilcox have dismissed claims that Williams was found in the holdall due to claustrophilia - the love of enclosure. Wilcox questioned why details of Mr Williams's private life were leaked to the press, furthering rumours of a 'cover up.'

His family described the salacious accounts as "horrible and completely fictitious."

Numerous experts have weighed in on whether it was possible that Williams would have been able to lock himself into the red sports bag, with one expert in confined space telling the inquest the feat would have been too much for "even Houdini" to master.

Peter Faulding said he had tried to lock himself in the holdall 300 times, adding: "My personal belief is that it could not be done."

Screengrab from a video reconstruction showing a person trying to close the zip and padlock in a sports holdall

However retired sergeant Jim Fetherstonhaugh and 23-year-old journalist Claire Hayhurst showed it was possible to lock oneself into a holdall.

Faulding, however, told the BBC: "A young girl zipping a bag doesn’t discredit this inquiry whatsoever. We were fully aware of other methods of being able to lock the bag but she or nobody could achieve it without leaving her DNA or trace on the bath and that’s the key to this."

Dr Wilcox has said it is "unlikely" that the mystery would ever be solved because of mistakes by investigators.

She said several factors hampered inquiries, such as breakdowns in communication by her own coroner's office, a DNA mix-up by forensics and the late submission of evidence by MI6 to police.

The police inquiry into his death continues.

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