The interior of 18 Alexandra Grove - highlighting the state of chaos and disorder in the alleged bomb factory.
This nondescript location in Leeds was alleged to have been the site of the 7/7 bombers' "bomb factory". Photographs published at the coroner's inquest show a chaotic scene of mixtures and equipment throughout the flat - including a bath full of proto-explosive and a kitchen cooker hob placed on an ordinary table.
The exact nature of the explosives seems to be a matter of dispute among the experts and the conspiracy-minded see this as an example of where the official narrative fails to be specific enough to rule out other alternatives.
A witness for the prosecution of the three men said to be allies of the plotters told Kingston Crown Court in 2008 that the explosives were: "unique in the UK and possibly the whole world" and it was unlikely the bombers worked alone:
"Although the information is available on the internet, I seriously doubt that this could have been done in complete isolation. They would have to do a lot of testing and it is very unlikely they would get it right first time. I suggest someone somewhere had information or advice."
Said to have been present at the flat were traces of HMTD (hexamethylene triperoxide diamine) - an organic primary explosive first synthesised in the 19th century. It has long been known to be unstable, difficult to store and actually unsuitable as a detonator in many cases, although superior to acetone-based explosives, which degrade quickly.
As you can discern, there is an interesting gap here between the allegation that the materials used by the 7/7 bombers were "unique in the UK" and the fact that HMTD is a well known explosive with a long history. While it is fairly stable once it has been made, during its creation it is highly volatile and difficult to mix.
Pictures of the flat show rooms in chaos - with explosives left in the bath, no sign of any refrigeration and very little sign of care or order of any kind. To those minded towards a conspiracy theory, this is suggestive that the idea of a sophisticated 'bomb factory' is a wild overstatement and that if the explosives did originate from this flat then they were not, in fact, "unique."
From there, some theorists speculate that the evidence at the flat was a relatively crude framing device to back up the story of the bombers as lone, self-starting agents.