"There were reports of a plane being both heard and seen by witnesses but again within minutes these reports were disputed. How the h*** could they know? The area was fully ablaze and no-one could get anywhere near to judge whether it was an accident or terrorists"
They could very quickly establish whether a plane was involved, without needing to be on site at all. This area is directly under the incoming flightpath into Luton, about ten miles from the runway. You can't just fly a plane into it without someone knowing about it.
I'm not jumping on any particular bandwagon, but here's one angle. If - IF - people who heard and/or saw a plane near the explosion site were correct, and my theory above of a plane dropping/shooting something on the leaked gas to cause an explosion is correct, the plane could be a small plane that didn't come from or land at that airport. Like a crop duster or other small plane. It looks like an agricultural area from pictures. I live in a rural area and there are more that a few really small little airports. Real small.
Not saying I believe any scenario more than another one. But I agree that for authorities to state, imply or say that an event is not terrorism, when it's too early to know with absolute assurance, is not reassuring.
What is the altitude at which planes "drop off" radar in that area?