Mother breaks down as MI6 says sorry for failures over spy's death

Mr Williams, a cipher expert, had carried out unauthorised searches on the MI6 website

Gareth Williams’ mother Ellen arrives for the inquest in London yesterday (Reuters)

MI6 yesterday offered a public apology to the family of Gareth Williams for the failure to investigate the disappearance of the intelligence officer whose body was later found in a padlocked bag in his London flat.

Mr Williams's mother, Ellen, broke down in tears after a Secret Intelligence Service (MI6) official – called Witness F – told an inquest into his death that her son's immediate boss, who admitted he had not followed procedure, had not faced any disciplinary action.

Witness F said: "We are profoundly sorry about what happened. It shouldn't have happened and we recognise delay in finding Gareth's body has made it even harder for the family to come to terms with his dreadful death and we are truly sorry for that. I also appreciate the delay had some impact on the police investigation."

The inquest at Westminster Coroners' Court heard the delay meant it could not be ruled out that Mr Williams was poisoned. Traces of a drug matching the party drug GHB was found in his blood. Forensic scientist Denise Stanworth said because up to nine days had passed after his death before his body was found "we cannot rule out volatile agents".

She added it was impossible to say if there was any sign of the legal high "poppers", acknowledging the drug "could have caused loss of consciousness or death". She also stressed, however, the symptoms are likely to have appeared naturally after Mr Williams' death.

Anthony O'Toole QC, for the family, accused MI6 of a "total disregard for Gareth's whereabouts and safety". He blamed the delay for preventing the family from saying goodbye to Mr Williams while his body was in an "acceptable form" and for making it more or less impossible for police to establish how he died.

"Because of the decomposition of the body, any forensic evidence that could have been derived from it has disappeared, so the police investigation has in essence been almost defeated," he said. It emerged at yesterday's hearing that Mr Williams, 34, a cipher expert, had carried out unauthorised searches on the MI6 website and this, according to Witness F, could have "theoretically" put him at risk from "hostile and malign" forces.

However, Witness F maintained that evidence of Mr Williams's sexual practices, which included him visiting 'claustrophilia' and bondage and sadomasochism websites, and the discovery of £20,000 worth of female designer clothing at his home would not have made him a security risk. Mr O'Toole told Witness F of speculation "that revelations about Gareth's private life might have rendered him unsuitable for SIS work". Witness F responded "There's no set template as to what (an employee's) lifestyle should be. Individuals have lifestyles and sexual choices which are perfectly legitimate."

At an earlier hearing Mr O'Toole said the family believed Mr Williams may have been executed by secret agents specialising in the "dark arts" with a cover-up organised to ensure his killers did not face justice. But Witness F insisted an internal review found there was "no evidence of any specific threat to Gareth and we concluded there was no reason to think his death was anything to do with his work".

Witness F said Mr Williams was "a fully deployable, highly talented officer" who had passed exams to carry out difficult covert work six months before he was found dead in August 2010. He had only been deployed in the UK, and not in Afghanistan or Russia as some media reports had claimed. He was on secondment with MI6 in London when he died but he had requested to return to his role at GCHQ, which had been accepted.

The inquest continues.