At least two people have been killed and scores injured after three blasts on the Underground network and another on a double-decker bus in London.

UK Prime Minister Tony Blair said it was "reasonably clear" there had been a series of terrorist attacks.

He said it was "particularly barbaric" that it was timed to coincide with the G8 summit. He is returning to London.

An Islamist website has posted a statement - purportedly from al-Qaeda - claiming it was behind the attacks. http://news.bbc.co.uk/2/hi/uk_news/england/london/4659093.stm