BRITAIN stood united last night in defiance of the bomb attacks which killed at least 52 people and left 700 injured as the reality of the War on Terror came to London.

Less than 24 hours after the capital had celebrated winning the Olympics, a 56-minute series of explosions blasted the Underground and a bus in what was thought to be an al-Qaeda attack.

Tony Blair stood shoulder to shoulder with world leaders at the G8 summit, opposition politicians and church and Muslim groups in condemning what he called an act of barbarity.

The first attack came at 8.51am in a tunnel near Aldgate station. Five minutes later, at least 21 people died in a blast in a tunnel between King’s Cross and Russell Square. At 9.17am, an explosion smashed through a tunnel wall at Edgware Road station, damaging three trains.

Exactly 30 minutes later, a fourth bomb went off on a No 30 bus, packed with commuters forced above ground after the Tube was closed.

The number of confirmed deaths was 37 — 21 at King’s Cross, seven at Edgware Road, seven at Aldgate and two on the bus in Tavistock Place. But the full toll will not be known for some time and sources said that at least another 15 had died in the bus bombing.

A leading London doctor, Professor Philip Patsalos, 52, was named among those seriously injured, after losing a leg in the King’s Cross blast.

This is the worst terrorist attack in Britain. The previous highest toll was in the 1974 IRA Birmingham pub bombings, which killed 21.

The emergency services were stretched to the limit by a series of bomb alerts and thousands of commuters were stranded after train and Tube services shut down. Transport for London promises a service this morning but there will be restrictions. Body scanners which can see through clothing will be introduced at some Underground stations.

A group calling itself the Secret Organisation Group of al-Qaeda of Jihad Organisation in Europe claimed the attacks on an Islamic website.

Investigators believe that the bomb on the double-decker bus may have been set off by a suicide bomber or may have gone off en route to its intended target. Tony Blair left the G8 summit at Gleneagles to fly to London for a meeting of the emergency Cobra planning team.

In a televised statement from Downing Street, Mr Blair said that the terrorists were “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”.

He added: “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, we will not be changed.”

George Bush, speaking from Gleneagles vowed that the terrorists would be brought to justice.

The Queen spoke of her shock at the dreadful events and will visit people caught up in the tragedy today. The Union Jack over Buckingham Palace was lowered to half-mast.

Rudy Giuliani, the Mayor of New York at the time of the destruction of the World Trade Centre, was near Liverpool Street station when the bombs exploded. In a letter to The Times today, he says: “Great Britain was there for us on September 11, 2001, and you should know that the United States supports you in your time of need.” There was no intelligence warning about the attack and the national state of alert had recently been reduced.

Scotland Yard denied last night reports from America that two unexploded devices had been found. They would also not comment on reports that the traces of high explosive found after the blasts was RDX, a key component in the Madrid bombings.

Mr Blair’s statement said that those responsible would have believed they were acting “in the name of Islam”. His words followed consultations with senior security officials and The Times understands that the Government’s “working assumption” is that al-Qaeda is responsible. Mr Blair has been told that there is no firm evidence yet of a suicide bombing.

Jack Straw, the Foreign Secretary, went further last night saying that the attacks had a ruthlessness that “bore all the hallmarks of Al Qaeda”.

Security is stepped up across globe

THE attacks triggered a worldwide terrorist alert. From Europe to America, the Middle East and Russia, countries put their forces on alert and stepped up security on public transport networks.

In France, Dominique de Villepin, the Prime Minister, advised travellers to avoid London until further notice. Two Cabinet sessions with defence and interior ministers were held to co-ordinate French emergency plans and offer help to Britain.

In Madrid, which suffered similar attacks last year, José Luis Rodríguez Zapatero, the Prime Minister, ordered the Interior Ministry “to activate all the systems of alert and prevention”, and told the security services to co-ordinate the hunt for those responsible for the British authorities.

Michael Chertoff, the head of the American Homeland Security Agency, raised the threat level “from code yellow or elevated to code orange, high” on transport systems. The US Embassy in London was cordoned off for a block around the Mayfair building.

Reporting team: Tom Baldwin, Rosemary Bennett, Steve Bird, David Charter, Liz Chong, Valerie Elliott, Alex Frean, Mike Horsnell, Ben Hoyle, Suzy Jagger, Sophie Kirkham, Adam Luck, Jack Malvern, Stefanie Marsh, Tim Martin, Sean O’Neill, Lewis Smith, Xan Rice, David Rose, Helen Rumbelow, Tosin Sulaiman, Rajeev Syal, Stewart Tendler, Nicola Woolcock, Fran Yeoman

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