More analysis on London
Some more breaking analysis from Mike Hough at South Africa's Institute for Security Studies.
"An Al-Qaeda attack in London was long expected as it had often been threatened. As to who was to blame and what their motive was, "there was a range of possibilities". Hough said there were 600 incidents of terror last year. That was a sharp rise from the average of about 200 a year before. Another new aspect of international terror was sympathisers acting on their own. This was the case with Abu Musab al-Zarqawi's branch of Al-Qaeda in Iraq. "It is a hallmark of modern terrorism that no one takes responsibility for such acts or only after an interval." As such he believed the attack was aimed at disrupting public life. The shut down of the city's tube and bus system as well as heightened security alerts throughout Europe afterwards would support this view. Hough said he would not assume the attacks were meant to disrupt the G8 summit that started in Gleneagles in Scotland on Thursday. If Al-Qaeda or fringe anti-globalisation activists wanted to do that they could have staged attacks closer the venue."