London Bomb Was 21/7, Not 7/7

At around 0820 hours this morning, as hundreds of thousands of Londoners were on their way to work, what appears to have been an Improvised Explosive Device partially detonated on board a City-bound District Line train approaching Parson’s Green station in the south-west of the capital. This station is on the Earl’s Court to Wimbledon branch of the District Line, and is above ground, on a viaduct.

A Sub-Surface Lines train, similar to the one at Parsons' Green

There were therefore none of the problems associated with having to evacuate a train in a tunnel. Moreover, although there was a flash fire and several passengers received burns on parts of their bodies, the force of the blast was minimal. Had it been a significant explosion, the train on which it took place would not look like it does now - needing no more than a good clean before it returns to service.

But the IED most likely could have been far more destructive: as the Evening Standard has reported, “Sylvain Pennec, a software developer from Southfields, near Wimbledon, said he was roughly 10 metres away from the explosion, describing the object as at first looking like a ‘bucket of mayonnaise’”. This is a significant clue.

Aftermath of today's incident: a flash and no bang

The Guardian told readers “Rory Rigney said he had just got on the tube train when the explosion happened only a few feet away … [he said] ‘It smelled like a fire extinguisher and there was this foam on the floor. It looked like foam from a fire extinguisher.’ He described seeing red wires coming out of a bucket in a Lidl plastic bag”.

So no, there were no serious injuries, but it could have been far worse. To see how much worse, we need to look back at the July 2005 bombings - the ones on 7th July which caused more than 50 deaths, and the attempted follow-up on 21st July, which succeeded only in covering those responsible in rather more than embarrassment.

The 7th July bombs detonated as they were designed to do: the damage to Underground trains of the kind which used to pass through Parson’s Green - those have all since been retired from service - was considerable. Windows were blown out and bodysides bent out of shape. No such damage occurred this time. Because the device didn’t go off properly.

Aftermath of bungled 21/7 attack - a puddle on the floor

When the 21st July bombers’ devices failed to detonate, all that was found in their rucksacks was not unlike what passengers saw after today’s incident. It turned out to be a mixture of chapati flour and hydrogen peroxide, a home-made liquid explosive. The high-explosive detonators failed to set it off, as it seems the bombers’ mastermind had a basic maths fail and didn’t calculate the ratio of ingredients properly.

All that resulted was a pool of pale yellow liquid on a Tube train floor - like the “bucket of mayonnaise” or “foam from a fire extinguisher” seen today. So what resulted was a 21/7, not a 7/7. But it’s almost certain that the intent was for it to have been the other way about.

And that is why the Police and security agencies are treating this morning’s incident with the utmost seriousness. Because it could have been one heck of a lot worse.