A UK coroner has concluded that Gareth Williams, the British spy whose naked body was found padlocked in a bag in his bathtub, was probably unlawfully killed.
Coroner Fiona Wilcox said she was sure a third party locked the code-breaker inside the red holdall in which his naked body was found in his bathtub.
Police strongly suspect a member of MI6 or GCHQ (Government Communications Headquarters) was in his flat the day he died and will take DNA samples from up to 50 of his colleagues, the Daily Mail reported.
Wilcox said he was probably killed and it "remained a legitimate line of inquiry" that the secret services may have been involved in the death.
She had earlier said there was not enough evidence to deliver a formal unlawful killing verdict.
The verdict was highly critical of the Metropolitan police's counter-terrorism branch and MI6, The Guardian reported.
Wilcox severely criticized Williams's employers at MI6 who failed to report him missing for seven days when he did not turn up for work.
She said she could "only speculate as to what effect this [delay] had on the investigation."
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The head of the intelligence service, meantime, made an unreserved apology to Williams's family over the delay in reporting him missing and the subsequent anguish it caused.
The BBC cited intelligence expert Crispin Black as saying that a cover-up by British secret services could not be ruled out.
"There's a possibility there's been some sort of clean-up by MI6 — that's a clear possibility," said Black, an intelligence analyst and former advisor to the UK government.
"One thing I'm pretty sure of, and I think others will be too, is that the police are unlikely to have been the first people around to that flat."
The 21-month investigation into Williams' death has yet to yield a suspect.
Forensic experts are hoping for a breakthrough from DNA tests on a green towel discovered in his kitchen.
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