Adviser was forced to live in safe house as frenzy grew

The phone calls to David Kelly's home and office from journalists began shortly after the BBC report which sparked the controversy over whether the Government had "sexed up" its Iraq dossier.

At first the calls were tactful approaches from specialist reporters, many of whom Dr Kelly had spoken to unofficially over the past 10 years for guidance on the issue of arms control, to ask whether he was the "senior British official" cited by the BBC.

By early this week, the media maelstrom had become so intense that Dr Kelly moved to a secret address. To add to his discomfort, newspapers on Wednesday were full of reports lampooning his performance before theForeign Affairs Select Committee and pointing out his resemblance to Britain's most prolific murderer, Harold Shipman.

For the media, the notion of a mole within the higher echelons of Whitehall with the power to damage the Government was impossible to resist. Within hours of the original BBC report by Andrew Gilligan on 29 May a race was on to find the latterday "deep throat".

It was not long before the name of a quiet microbiologist and Ministry of Defence consultant was circulating among a few specialist reporters.

A number of newspapers approached Dr Kelly before his name became public on 9 July. He denied being the source of the BBC report but within days he had approached his line manager to confirm that he had met Mr Gilligan. His anonymous existence was transformed into a life under full-blown scrutiny.

After abrasive questioning by MPs on Tuesday, during which he had spoken in a voice barely above a whisper, the arms control expert had to deal with the verdict of the media. The Daily Mail labelled him a "quivering boffin", others called him "evasive", while The Guardian remarked upon his likeness to Dr Shipman.

It is understood that he spent much of the past 10 days at a safe house provided by the MoD, returning occasionally to his Oxfordshire home until Thursday, when he returned for the last time.

His friends said the media had to ask itself about its role in his death. Tom Mangold, a television journalist and friend of Dr Kelly, said: "He is dead because of something that happened in journalism which means that we all have to look to our consciences."