In the Mirror’s scenario the master bomber cynically tricked his team into thinking that when they pressed the button, they were setting off a timing device that would give them sufficient time to leave the target area. Instead, they pressed the buttons, detonated the bombs and killed themselves as well as their victims.

According to this scenario the bombers were merely expendable low-level operatives whose death would happily remove the probability that, if caught, they would reveal, under interrogation, details about their controllers and other members of the network.

In its way, this admission is a breakthrough that should allow other more plausible scenarios to emerge for investigation.

In that spirit, let me suggest variants of the “dupes scenario” that I believe are at least equally plausible, given the information currently available to the public .

It’s necessary to understand that the detonators were probably constructed from mobile phones. Mobiles can be used to set off bombs in three ways: by using them as a timer (alarm clock function) or by remote detonation using voice or text message. While unidentified police sources have claimed that no “timers” have so far been found, The London Times had admitted the possibility of mobile phones being used.

There are many problems with the version of the dupes scenario publicized by the Mirror.

If the four men knew they were carrying bombs and believed they were going to plant them before withdrawing safely from the scene it would certainly have occurred to them that the police would afterwards be searching for four men of Islamic background and that they would be recorded on CCTV arriving at Luton, then at Kings Cross and then going their separate ways. They are hardly likely to have ignored this threat. They would certainly have traveled separately and approached the targets from different directions. They would not have blithely assumed they could meet up again at the rented car at Luton to drive home. Nor would they have left more bombs in the car as suggested by some media reports.

The Mirror’s scenario also depends on the three tube bombers (and probably all four of them) activating the bomb timers (perhaps by pressing a button) at an agreed time and unwittingly blowing themselves up. But why would they operate in that way? If the aim was to leave the bombs on the trains – surely the most effective target in terms of death and chaos – then the bombers would have activated the timers as the trains were pulling into a station then got off at the last moment leaving the bombs on board. But in that case, they would all have unwittingly detonated the bombs just as the train was approaching a station.

No, the simplest and most compelling reason for the near simultaneous detonation of the three tube bombs is that the bombs were detonated by timers, and that timers were set running, by some method, at Kings Cross station.

The master bomber’s backup

It is entirely plausible that the master bomber would not have relied solely on the timer. If a timer failed to detonate one of the bombs, a dupe would be left alive and in possession of the evidence. A simple fail-safe detonator might also have used a mobile phone, perhaps the same one used as the timer in each of the bombs. The London Tube system is not equipped for mobile phone reception, but if the master-bomber backed up the timer by sending a text message to the four bombs, the message would have been delivered to the bomb detonators as soon as the unwitting bomber left the underground and entered a mobile phone reception area on the surface.

In my variants the four dupes were recruited to carry out some task, other than a bombing, which involved them going to Luton, where they picked up the bombs, securely packaged to prevent their real contents being detected by the men, then to Kings Cross, where they received further instructions. The purpose for which they were recruited might have been either legal or illegal.

Illegal purposes

* A drug courier run, for which they were promised big money.
* A secret courier task, related perhaps to clandestine support for, say, the Iraqi resistance or a Palestinian group.

In either case the dupes were instructed to proceed to Luton, then by train to Kings Cross to meet a contact who was probably unknown to them, but who, they were assured, would recognize them when they got off the Luton train. This person would tell them where to deliver the stuff. It’s unlikely they would have been given an address to go to. They would have been told to travel individually to four separate destinations – such as the entrance to another railway station – where they would be recognized by the person they were to give the backpack to. That scenario is consistent with standard clandestine operative technique.

Based on what we know of the character and background of the four, I’d rule out the idea that they thought they were drug couriers. More likely, I believe, is that the manipulator would have played on their political and religious sympathies and their sense of adventure. They would have been told they were transferring something important (guns, munitions, currency, explosives – exactly what would probably have been left to their imagination) to separate locations in London for onshipment to the final recipient – possibly the Iraq resistance or a Palestinian group.

Note that in this variant the manipulator might be either an agent provocateur working for Mossad, an American or British secret police faction, or a genuine Islamist, but the cynicism of the manipulation suggests a state operation, rather than that the men were duped by one of their own.

Legal purposes

* A security training exercise. This variant has already been flagged by skeptics. In it the dupes were offered good money to be "the enemy" in a security training exercise played out in the underground and were naive enough to believe the recruiter. They would have been engaged as actors and told they were only required to carry the backpacks to certain destinations to see if they could get them through the security people under training who had been given the “profile” of a suspect. They would also have been told that, for security reasons, they were not under any circumstances to talk to anybody else about the exercise. As a further precaution they would have been told they’d only be informed of their destination when they were briefed at Kings Cross station. They would probably have been told to meet back at the station for a debriefing. Such exercises are a normal part of security training, but we might question whether, in the atmosphere generated by Britain’s role in Iraq, four young Muslims would have been happy to take part.

Arming the bombs

Whatever method was used to dupe the men, they arrived with the bombs at Kings Cross station where they met a contact and were assigned their tasks.

In the case that the men thought they were engaged in a non-legal task, examination of, or tampering with, the backpacks by the contact, who they probably would not have known, would have run the risk of arousing their suspicion. So how, in that case, were the timers activated?

This could easily have been accomplished by the master bomber, or more likely an unseen accomplice, using a modified TV, stereo or garage door remote control. Rigging a remote to turn on and to activate the alarm clock function on a mobile phone would present no difficulty to a techno-terd of average ability.

Why did the fourth bomb explode on the bus?

The mobile phone detonator scenario also provides a plausible explanation for Hasib Mir Hussain’s bomb exploding on the No. 30 bus an hour after the tube bombs.

When the phone-based detonator attached to the bomb he was unwittingly carrying was remotely switched on, the alarm clock function failed to activate. So the bomb failed to detonate twenty minutes after activation and he left the tube either because his train hadn’t arrived (it has been hypothesized that he was supposed to travel on the Northern Line which had been disrupted by technical problems) or he was evacuated from the tube after it ground to a halt in the aftermath of the bombs.

Perhaps he tried to reach his appointed destination by bus. Perhaps he caught the No. 30 to do a little sightseeing. Why not? He’d heard that the whole underground had been knocked out by some sort of a power surge, London was in chaos. He couldn’t contact the man he thought was his controller for the exercise (or in the illegal purpose variant, his London contact) because the phone network was down. And he didn’t know where his three friends were.

As the master bomber listened to the incoming news reports (and perhaps other intelligence) he would have realized that only three bombs had gone off. This would have been a bad moment. Somewhere, out there, was a dupe, still alive and carrying the evidence. If he hadn’t already sent the text message to the bomb detonator, he now did so. But the mobile network was in such chaos that it took another hour before the message was delivered to the bomb on the No. 30.

Keep it Simple, Stupid

The variants of the dupes scenario I am suggesting do not require a large conspiracy in the operational phase. The whole job might have required (apart from the dupes):

* An agent provocateur, to recruit the four.

* A master bomber to plan the operation, supply the bombs and rig the detonat/p>

* An assistant to remotely activate the mobile phone detonators at Kings Cross.

That’s a nice tight little cell of just four conspirators, or perhaps only three if the master bomber doubled as the contact at Kings Cross or as the unseen assistant. It’s easy to organize, very hard to detect and has a very low chance of failure. An organization such as Mossad would have no difficulty finding three or four hardened bastards for the job … and an overwhelming interest in provoking world outrage against Muslims.