Why would a group of young men carry four backpacks to different parts of the public transport system if they didn't know what was in them? I can admit the possibility that they didn't intend being suicide bombers, but completely innocent patsies seems unlikely to me. It would be less awful if they weren't suicide bombers, but thought they were transporting bombs to sites where they would detonate after warnings (for instance).
If they were completely innocent, they picked up bags from someone, drove to Luton, took the train to London, spilt up and went in different directions on fairly precise timings. Why didn't they look in the bags? Why didn't the whole set-up just seem weird?
If they were, for the sake of argument, trained fanatical cultists (if they were Christian, we'd call them cultists) then why would they tell people around them their beliefs?
As for looking in the bags, they were quite large. There's an enormous amount of possibilities such as perhaps the bombs were in the bottom and more innocuous material was on top. The police reports I've seen said the bombs weighed just 10 pounds (4.5 kilos), which you don't need a large camping rucksack to carry a bomb of that size.
I was however intrigued on the reports of timers or not. Did they find timers or didn't they? It's fairly unlikely that an innocent passenger had a washing machine timer in his/her pocket but I guess it's possible...
And why did they leave explosive material behind in the Fiat in Luton? The police detonated it in nine series, which seems like a lot if it was just "trace" evidence.
We'll just have to see what comes out as the investigation continues, just like you said.
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