Monday, 7 December 2009

21/7: devices not capable of exploding

On Tuesday 1st December 2009, ITV1 presented "Bombers on the Run" in its Real Crime series, describing the case of the incidents on the London transport system on 21st July 2005.

The last section of this programme covered the related court case in 2007, but omitted some important details.

The prosecution case on the explosives was presented, including the assertion that 70% hydrogen peroxide devices detonated explosively every time in tests. The video footage that was shown in court of one of these test explosions was shown in the programme.

The defence testimony of Professor Hans Michels, who stated that the devices used on 21st July 2005 were not capable of exploding, was not mentioned by the ITV programme. This testimony had a significant effect upon the trial because it resulted in the prosecution dropping the charge of conspiracy to cause explosions likely to endanger life.

The programme also failed to mention the significant assistance given to the prosecution by the cut throat defence of mysterious defendant "Asiedu" (who claimed he had abandoned the device found in a park in Wormwood Scrubs). His true identity has never been formally established; in a Ghanaian news article two people claiming to be his biological parents state that he is Ishmael "Sumaila" Abubakar and that they had contact with UK security operatives. If so, it is very strange that he was tried under the alias "Asiedu" when the UK authorities knew his true identity. Curiously, at one point "Asiedu" tried to join the British Army.

According to a BBC Report:

At times during the 21 July trial earlier this year the barrister for Manfo Kwaku Asiedu was landing heavier blows to his co-defendants than the prosecution.

It was Asiedu's counsel, Stephen Kamlish QC, who actually made the link between the 21 July plot and the 7 July attacks.

That was a line of attack which even the prosecutor, Nigel Sweeney QC, had chosen not to go down.

In fact, during legal argument out of the jury's earshot, at least one of the other defence barristers suggested Asiedu and Mr Kamlish be excluded from the trial.

Without this "defence", the prosecution may not have been able to secure the convictions for conspiracy to murder against the four principal co-defendants.

The jury could not reach a verdict on "Asiedu", but before the re-trial "Asiedu" conveniently pleaded guilty to conspiracy to cause explosions (the charge that had been dropped in the first trial, presumably because the prosecution were no longer confident that the evidence proved guilt beyond reasonable doubt after the testimony of Professor Hans Michels). Coincidentally, the charge against "Asiedu" for conspiracy to murder was dropped. Since plea bargaining is technically illegal, this can only have been a coincidence!

The ITV programme omitted the similar assistance given to the prosecution by the alleged confession of defendant Hussain Osman. This occurred after submission of evidence in the trial had concluded, but the judge stopped the closing speeches and allowed the case to be re-opened so that the "confession" could be admitted as evidence. The "confession" was not provided in court by Osman himself, but by two prison officers who claimed to have heard it. The judge did not permit defendant Muktar Ibrahim's lawyer to cross examine this evidence, ruling that it was "irrelevant" to the case against Ibrahim, even though the substance of the confession was that "Ibrahim was the brains behind making the bombs and trying to destroy parts of London" and that "Ibrahim had bullied [Osman] into making the bombs and the distribution of such items"!

The ITV programme also showed footage of a liquid boiling in a saucepan, whilst the narrator informed us that the "bombers" boiled the dilute hydrogen peroxide in order to increase its concentration. We can be fairly sure that the boiling liquid shown was not, in fact, hydrogen peroxide since the vapour produced would be liable to detonate spontaneously, just as it would have done in the "bomb factory" if the "bombers" had been boiling it.

Whilst the trial was in progress, there was an interesting thread on AnswerBank:

Tube bombers, Hydrogen Peroxide Reaction?

Any one else a bit curious about the composition of the explosive that the tube bombers have been reported to use? I have worked using concentrated Hydrogen Peroxide ,100 vol, to decompose organic materials for analysis.

I can not understand how a mix of concentrated Hydrogen Peroxide and flour did not begin reacting as soon as it was mixed. I would have expected such an unstable mix to spontaneously ignite, there would be no chance to transport it any where. Also , how did they concentrate the Peroxide? the reported answer that they boiled down huge quantitys of dilute peroxide on a kitchen stove also seems unbeliveable!

In my expierience Hydrogen Peroxide decomposes and loses Oxygen on heating, you end up with water!

It is many, many years since I worked with 100 vol Hydrogen Peroxide so prehaps my memory is not as good as it was but every time I read about this story it gives me an uneasy feeling that we are not being told the full truth. Any one like to comment ? , Prof, we could do with your insight and knowledge on this!!

The response of "Prof" is illuminating, especially as he appears to be convinced of the guilt of the defendants, calling them "criminals" and "idiots":

I'll start by saying that like you, I was extremely sceptical about the lack of any reaction between the concentrated hydrogen peroxide and the chapatti flour when I read the press reports. Like you, I thought that spontaneous ignition should have occurred if the conditions were reported correctly in my copy of The Daily Telegraph. Here’s another report that’s more enlightening:,20867,21071971-2703,00.html

Hydrogen peroxide does indeed lose water on heating and decomposes into water and oxygen. Because of this, concentrating the stuff is not easy and requires considerable expertise as well as equipment. The usual method employed in concentrating the stuff commercially is via specialised vacuum distillation, but these people don’t seem to have had the skill or equipment to carry out this method and although I won’t go into details, believe me, it’s not an operation that can be carried out over the kitchen sink. Even laboratory vacuum distillation is hazardous..

Concentrating “concentrated” hydrogen peroxide solutions in a kitchen environment is not viable because if the correct temperature and pressure is reached, the vapour will either detonate or ignite with catastrophic consequences.

Other methods of concentration do occur, but again you need the equipment and expertise. No mention of such equipment has been made and only one of the criminals seems to have had anything like a rudimentary general science college education.

Either way, it could be said that if these idiots poured the neat hydrogen peroxide as purchased into a saucepan and did nothing else, “concentrated” hydrogen peroxide could be said to be in the saucepan, simply because it’s stronger than the OTC product. The strength of the processed hydrogen peroxide has not been disclosed.

With regard to Law Student's point, I can think of a number of explosives with shortened names, some of which are colloquially referred to by the name or acronym of one of the components. However, I very much doubt that the press were referring to the finished mixture in this way when they discussed the peroxide. Why refer to it as such? When you mix sugar and salt, I doubt whether the press would refer to the combination as salt (or sugar). The press do try their best to be reasonably accurate when describing substances to avoid criticism.

It’s also incorrect to consider that because peroxide stability increases with molecular weight, the mixture is more stable. It's not always the case. Furthermore, the nature of the fuel also needs to be taken into account. Only then can the stability of the resultant “peroxide” be assessed.

Like Mortartube, I'm inclined to think that acetone peroxide or its homologues were involved here.

We have yet to be given a credible explanation of how concentrated hydrogen peroxide could be produced in a domestic kitchen, and this is as true for the July 7th and airline plots as it is for the July 21st incidents.

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