By NORMAN BAKER

Last updated at 08:14 22 October 2007

But the crusading MP Norman Baker felt sure there was something more to his death - and gave up his front-bench role to investigate the case.

In the Mail he revealed extraordinary evidence that he believes proves Kelly did not take his own life and was instead murdered by Iraqi dissidents. Here, he reveals how the murder may have been carried out . . .

While investigating the death of Dr David Kelly I have made many strange discoveries, not least some disturbing parallels with the case of a young American journalist named Danny Casolaro.

Mr Casolaro made himself deeply unpopular with elements in the murky world of U.S. defence by probing too deeply into their activities.

One morning in August 1991, he was found dead in a hotel room near Harpers Ferry in Virginia. He was in the bath, naked, with his wrist slashed.

There were no signs of bruising or other marks on the body and the police concluded that he had committed suicide.

But this was totally false according to Dr Christopher Green, who was the CIA's chief forensic pathologist for decades.

Dr Green participated in Casolaro's autopsy and last year he told veteran White House reporter Sterling Seagrave that the young journalist had been killed before being stripped, put in a full bath, and his left wrist cut in precisely the same manner as Dr Kelly's.

And as with Dr Kelly, there was remarkably little blood, bar a small amount smeared on the edge of the tub, suggesting that the wrist wound had been inflicted after the heart had stopped pumping.

This compelling demonstration of how effectively a murder can be disguised as suicide drove me on in my search for the truth about Dr Kelly, who was found dead in an Oxfordshire wood on July 18, 2003, having apparently taken his own life.

Before Danny Casolaro died, the journalist had been investigating the activities of America's private security companies which, according to Sterling Seagrave, are linked to the 'Grey Ghosts' - an army of professional killers commissioned by the Pentagon to carry out assassinations.

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The similarities between the two men's deaths led Seagrave to suggest that Dr Kelly might also have fallen victim to these shadowy figures.

After all, he was the source behind a BBC report that the British government had 'sexed up' intelligence about Saddam Hussein's weapons of mass destruction in order to justify the invasion of Iraq. This can hardly have been well received by the White House.

As I explained in Saturday's Mail, my own information strongly suggests that those behind Dr Kelly's death were Iraqi dissidents opposed to Saddam Hussein's regime and angry at Dr Kelly for undermining the case for toppling him.

A well-placed source also told me that the British police or security services had been warned of a likely assassination attempt but were not in time to stop it.

Did they then try to disguise the murder as suicide for reasons of political expediency?

To understand what may have happened, we must return to Thursday, July 17, the day

Dr Kelly disappeared. That morning he was at home with his wife Janice in the village of Southmoor and it must be said that none of his behaviour fits the profile of a man about to commit suicide.

In her evidence to the Hutton inquiry into Dr Kelly's death, his wife said he was 'tired, subdued, but not depressed'. Indeed, it seems it was Janice Kelly, not her husband, who was more seriously under par.

During phone calls that morning, Dr Kelly told a colleague that he was basically 'holding up all right', but that his wife was having a difficult time, both physically and mentally, under the pressure of long-standing ill health and the political storm that had engulfed them.

At lunchtime she went to bed with a nauseous headache and arthritis pains. He, on the other hand, appears to have carried on working normally, eaten some lunch and taken the trouble to go upstairs to check on his wife, shortly before 2pm, to see how she was feeling.

Given his obvious concern, it hardly seems likely that he would want to exacerbate matters for her by committing suicide that day.

Dr Kelly told his wife he would be going out for one of the regular walks he took to help his bad back. These were normally short affairs lasting no more than 25 minutes.

Mrs Kelly estimates that her husband left the house shortly after 3pm. With him, we are led to believe, he had the knife later found by his corpse and three packets of the painkillers his wife took for arthritis. These would later be discovered in his jacket pocket - empty but for one of the 30 tablets.

According to the Hutton inquiry, Dr Kelly set out on that walk intent on killing himself.

But, if so, why does he appear to have waited so long before doing it?

Since the pathologist inexplicably failed to take Dr Kelly's body temperature when he first arrived on the scene the following day - a standard procedure which would have helped give an accurate time of death - we have to make our own deductions about when he died.

The pathologist offered a wide window of between 4.15pm on Thursday and 1.15am on Friday. But there is every reason to think this window is far too wide.

The Hutton inquiry heard that after Dr Kelly's body was found on Friday morning, two paramedics moved his arm away from his chest at about 10am so that they could attach electrodes and confirm that he was dead.

Clearly, rigor mortis - the stiffening of the body - had not yet fully set in. Since it is generally accepted that it reaches its peak after 12 hours, we can assume that Dr Kelly most likely died at some time after 10pm on the Thursday night, and quite possibly much later.

What then happened to him in the missing hours - at least seven of them - between leaving home and supposedly killing himself?

The last person known to have seen Dr Kelly alive was his neighbour, Ruth Absalom, who met him about three-quarters-of-a-mile from his home.

They passed the time of day briefly before going their separate ways. Dr Kelly's parting words were: "See you again then, Ruth."

According to Ms Absalom, he was heading towards the nearby village of Kingston Bagpuize.

That would be consistent with a circular half-hour walk back to his house - but in quite the wrong direction to reach Harrowrecords-down Hill, the lonely area of woodland where his body was discovered.

One of the few clues to what happened next is that Dr Kelly's phone was switched off when a colleague from the Ministry of Defence tried to call him between 5pm and 6pm.

This was odd. Dr Kelly himself would tell friends that his mobile was always on and, given that he had been in regular contact with the MoD that morning, and that the furore surrounding him was developing from hour to hour, it seems unlikely that he would have turned it off or let the battery run down.

If he did indeed intend to commit suicide, turning off his phone could be seen as a preliminary step. But for reasons I have made clear, I do not believe suicide is a credible explanation for his death.

This leaves us with an alternative possibility. Did someone else turn Dr Kelly's phone off so that his movements could not be traced via signal kept by the phone company? In other words, was he forcibly abducted?

If he headed in the direction Ms Absalom described, his walk would probably have taken him along Appleton Road, a quiet and rather empty stretch with only sporadic development alongside.

From there he is likely to have turned right into Draycott Road, which is even more deserted. A no-through road with some derelict buildings part-way down, it peters out into a footpath at the end.

On either of these roads it would certainly have been relatively easy for determined abductors to have forced the 59-year-old weapons inspector into a van without anyone seeing.

According to the information I have been given, the murder itself was carried out by a couple of not very well-paid hired hands.

As to the method used, I am told that they gave Dr Kelly an injection in his backside, which perhaps points to the use of succinylcholine, a white crystalline substance that acts as a muscle relaxant.

For less beneficent purposes, it can be used to induce paralysis and cardiac arrest and frequently goes undetected in post-mortems.

I asked Thames Valley Police whether the body had been checked for the presence of this or a similar substance. They told me that they did not know.

If this was not the substance used then, alarmingly, there appear to be a large number of other ways in which Dr Kelly might have been killed that would be difficult or even impossible to trace.

For this we can no doubt partly thank the work of Project Coast - a highly unpleasant chemical and biological warfare programme run by the South African government from 1981 onwards to develop exactly such capabilities.

With aims including the creation of a biological weapon designed to attack the black population while leaving whites unscathed, its prime mover was Dr Wouter Basson, variously described as 'the South African Mengele' and 'Dr Death'.

Ironically, in the week before Dr Kelly died, it is alleged he was due to be interviewed by MI5 about his links with Dr Basson, who in 1985 had visited the Porton Down research centre, where Dr Kelly was then head of the Chemical Defence Establishment.

This visit had happened at a time when Mrs Thatcher's government claimed that the South Africans were developing biological and chemical weapons solely for defensive purposes.

Only later was it revealed that they were working on chemicals such as parathion, an organophosphate that can be introduced into the body through hair follicles, perhaps under the arm or around the crutch.

This causes vomiting - evidence of which could be seen on Dr Kelly's body - and leads to a respiratory attack. It is extremely difficult to detect traces of such a chemical in the body, unless you know what you are looking for.

When I tracked down Wouter Basson at his home in the Western Cape earlier this year, I asked him if he thought Dr Kelly had been murdered.

He paused, as if choosing his words carefully, then replied that Dr Kelly 'didn't seem the sort to commit suicide'.

He was also in no doubt that the UK, and indeed other Western countries, have a capacity for assassination.

Other possible methods of killing Dr Kelly included the use of saxotoxin, found in some shellfish and known as the CIA Shellfish Toxin, after its alleged use by that agency to kill one of their targets. Even a tiny amount is effective seconds after injection and is completely untraceable after autopsy.

One private detective even suggested to me that Dr Kelly's killers might have made gruesome misuse of the equipment employed by undertakers in embalming, placing a tube into an artery and forcibly pumping the blood out of the body.

This would cause unconsciousness and then death, and reinforce the assumption that the victim had lost a lot of blood through a cut - the conclusion reached by Lord Hutton in Dr Kelly's case.

The detective told me that this process did not need access to a main artery like the jugular, but could be achieved through, say, the ulnar artery.

This was the one slashed with a knife in Dr Kelly's wrist. Was that incision an attempt to cover up the artery's previous use?

Another ghastly suggestion came to me from someone who signed themselves only as 'Nemesis'. Their letter alleged that he or she had been told by a 'member of the non-English diplomatic corps' that air had been introduced into Dr Kelly's bloodstream through a needle in a vein.

Apparently, if present in sufficient quantities, air in the major organs will kill and leave no scar. 'Nemesis' was in no doubt that this was how Dr Kelly's life had ended. "His heart and lungs were full of air," the letter said.

We know that the pathologist did retain one of Dr Kelly's lungs and some blood to test for substances such as chloroform but Assistant Chief Constable Michael Page, who gave evidence at the Hutton inquiry, revealed that the tests to the lung had not actually been carried out.

This was, he said, because no suspicious substances had shown up in the blood tests.

Whatever method might have been used to murder Dr Kelly, we have to wonder why those responsible did not kill him immediately. There would have been no insurmountable obstacles to doing so, after all.

Perhaps his kidnappers wanted an opportunity to take him into the woods at Harrowdown Hill under cover of darkness to minimise the chances of being spotted or disturbed.

It certainly would not have been difficult to have given him a shot to render him temporarily unconscious until his assailants forced him to walk to the spot where he would be killed and found the next day.

If they drove him there, the closest they could have got by road was about half a mile from where his body was found.

That walk is rather a public one, but there is another route and one seemingly not investigated by the police.

This path runs from a remote reach of the River Thames, about 500 yards away, up through a field and into the woods. With no houses or other dwellings nearby, anybody walking here is unlikely to be seen, particularly in the dead of night.

Intriguingly, this area was searched the following morning by Louise Holmes and Paul Chapman, the two volunteers who eventually found Dr Kelly's body.

They told the Hutton inquiry that some time after beginning their search at 8am they came across a group of three or four people in a boat and had a brief conversation with them.

Who they were, and what they were doing on the river at that time of the morning, has never been established. They could, of course, have been holidaymakers. But was the truth more sinister?