I was awoken by my mum telling me about this. People are reporting that they heard this in West London and as far as Maidenhead, Surrey, which is at least 40 miles away.
LONDON (Reuters) - A large explosion was reported north of London by witnesses ringing into British media early on Sunday.
One, identified only as Heather, said she had hear a loud blast near the commuter town of Hemel Hempstead and could see sheets of flame soaring into the sky.
"There is a fuel depot nearby," she told BBC Television. "There are lots of houses damaged."
Police were not immediately available for comment but another eye witness also said he thought there had been an explosion at the fuel depot although Luton airport is relatively nearby.
http://today.reuters.co.uk/news/newsArticle.aspx?type=topNews&storyID=2005-12-11T063632Z_01_FOR123780_RTRUKOC_0_UK-BRITAIN-EXPLOSION.xml
You guys have sure had your share of bombings. I read quite a bit about Bishopsgate in the early '90s. It did incredible damage.
How could a blast be "heard from 40 miles away?"