British prime minister Tony Blair pledged this evening his country would not be intimidated by the string of terrorist bombings across London.
A grim-faced Mr Blair promised intense police and security service action to bring the bombers to justice and he repeated his "profound condolences" to the families of the victims.
In a televised statement recorded in Downing Street, Mr Blair said: "It is through terrorism that the people that have committed these terrible acts express their values and it is right at this moment that we demonstrate ours.
"I think we all know what they are trying to do. They are trying to use the slaughter of innocent people to cow us, to frighten us out of doing the things that we want to do, trying to stop us from going about our business as normal, as we are entitled to do and they should not and they must not succeed.
"When they try to intimidate us, we will not be intimidated. When they seek to change our country or our way of life by these methods, we will not be changed."
On his return to London from the G8 summit of world leaders in Scotland earlier today Mr Blair said it was "reasonably clear" that London had been hit by a series of terrorist attacks.
“It is reasonably clear that there have been a series of terrorist attacks in London," he said.
“There are obviously casualties, both people that have died and people seriously injured. And our thoughts and prayers of course are with the victims and their families.
“It is my intention to leave the G8 within the next couple of hours and go down to London and get a report face-to-face with the police and the emergency services and the ministers who have been dealing with this and then to return later this evening.
“It is the will of all the leaders of the G8 however that the meeting should continue in my absence, that we should continue to discuss the issues that we were going to discuss and reach the conclusions that we were going to reach,” Mr Blair said.