MI6 bag death stumps coroner

Dr Fiona Wilcox, giving a narrative verdict at Westminster Crown Court, said Gareth Williams's death was "unlikely" to ever be explained.

Despite a 21-month police probe and a seven-day inquest, "most of the fundamental questions remain unanswered."

In a narrative verdict no cause is recorded, just the circumstances.

Mr Williams (pictured), a 31-year-old fitness enthusiast originally from Anglesey, was found naked, curled up in a padlocked holdall in the bath of his Pimlico flat on August 23 2010.

Pathologists said he would have suffocated within minutes if he was alive when he got into the 32 by 19 inch bag.

Poisoning and asphyxiation were the "foremost contenders" for the cause of death.

Experts said even Houdini would have struggled to lock himself in the bag.

Mr Williams's family lawyer suggested the "dark arts" of the secret services were behind the mystery.

Dr Wilcox strongly criticised spooks for not handing police evidence - including nine memory sticks and a mystery black bag - found on Mr William's desk at MI6 headquarters.

Lead detective Jackie Sebire was only told about them this week.

MI6 also examined Mr Williams's computers without telling police.

Ms Sebire said there was still something suspicious about the death.

And Dr Wilcox said it remained a "legitimate line of inquiry" that the secret services were involved in Mr Williams's death and criticised "shortfalls" by MI6 in passing on evidence to Scotland Yard.

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

Dr Wilcox said the "highly unusual circumstances" of Mr Williams's death had immediately raised the possibility of foul play, which had prompted "endless speculation."

Mr Williams's colleagues were interviewed but no formal statements were taken and Dr Wilcox said it "did affect the quality of the evidence that was heard before this court."

And confusion over a second post-mortem, a DNA mix-up and delays in spooks handing evidence to police all muddied the waters.