London has feared a devastating terrorist “spectacular” since 191 people were killed and more than 1,500 injured in the Madrid bombings in March last year.

Today’s series of multiple attacks across the capital – on the first full day of the G8 summit – bear all the hallmarks of al-Qaida’s style of terrorism.

Like previous strikes, including the September 11 attacks in the US, there were almost simultaneous blasts. And like Madrid, they came on a clearly significant day.

In the Spanish city, terrorists planted 10 bombs on four packed commuter trainHs just days before the Spanish elections, which ousted the right-wing government that backed the invasion of Iraq.

Al-Qaida-linked militants claimed responsibility.

A video found near a Madrid mosque after the attack claimed it was revenge for sending 1,300 troops to Iraq.

Terrorism expert Professor Eric Moonman told Sky News: ``It's where the normal public go day-to-day that is always an attraction for the terrorist mind.

“It’s a twisted mind and that’s why we’re finding that the heart of London is almost closed down.

“The bus is a public vehicle and this is what was found in Madrid and what the Israelis have to live with because they know it produces the most terrible and terrifying of pictures and it makes a story.

“We haven’t been up to the mark on this... nevertheless, this isn’t the moment to apportion blame.

“But there is a massive job to be done, confidence has to be restored and then we have to start to think about where they are coming from.

“The unfortunate thing is because of what is going on Scotland some of the twisted minds of the terrorists will all want to claim credit for this action.

“There will be a lot of people who will want to say we did it.”

The expert added: “The fact is, you can do any crime if you really want to.

“It is a bloody sight and it’s one I think will probably continue, that’s why the authorities are determined to keep people out of London because I don’t think we have seen the end of it today.

“It is still early morning and the co-ordination they’ve used is to wreck the day. It is quite conceivable they haven’t finished yet.”

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