LONDON -- Britain fell silent yesterday on the first anniversary of the suicide bombing assault on London's transit system -- a stunning strike that killed 52 commuters and wounded more than 700 in the country's deadliest attack since World War II.
Prime Minister Tony Blair, survivors, and city workers bowed their heads during two minutes of national silence observed from the Wimbledon tennis tournament to Scotland, a quiet punctuated by the solemn tolling of bells at St. Paul's Cathedral in the heart of London.
Mourners carried flowers and candles to makeshift shrines near the sites of the four bomb blasts. Reflecting the widespread feeling of unease that grips London, one person left a small note that read: ``We will never forget."
``This is a time when our country unites across all races, religions, and divides, and stands in solidarity with all those who have suffered so much, in sympathy with them and in defense of the values which we share," Blair said at Fire Brigade headquarters.
Relatives of the dead gathered later for a tearful private ceremony at Regent's Park, some reading poems to honor their loves ones. Names of all the victims were read as many in the crowd wept and people lined up to place yellow flowers in a mosaic memorial.
Before last year's attack, Britain had not seen a major terror strike since 1974, when the Irish Republican Army set off bombs outside two pubs in Birmingham, killing 21 people.
Metropolitan Police Commissioner Ian Blair said yesterday that Britain faces the likely prospect of another attack. ``There are, as we speak, people in the United Kingdom planning further atrocities," he told BBC Radio. ``Since July, the threat has palpably increased."
The Sept. 11 terror strikes on US soil ushered in a new era in terrorism in the West. The attacks have led many to wonder whether, in the post-Cold War era, the world is gripped by another clash of civilizations: one in which the values of Western liberal democracies are in irreconcilable conflict with those of militant Islam.
For Londoners, the attacks have shaken -- but not entirely overturned -- a conviction that the two cultures can coincide peacefully in the vibrant multicultural capital.
Still, the background of the bombers came as a shock to Britons: The four bombers were all British citizens raised in northern England. Three were of Pakistani descent and the other was a Jamaica-born convert to Islam.
Residents woke yesterday to the sound of police helicopters hovering over the city, but Londoners made a determined effort to continue their daily routine.
Buses and subway cars had standing-room only during the morning rush hour. The atmosphere on the Underground was tense and subdued, as the city was reminded of the 52 people who never made it to their destinations last July 7.
Memorial plaques were unveiled at each of the three Underground stations affected by the attacks. Flowers were laid and candles were lighted at the sites.
The first blast occurred at Aldgate station, when a suicide bomber detonated his explosives at 8:50 a.m., killing seven people. Minutes later, a bomb exploded at Edgware Road, killing six. A third bomb killed 26 between Russell Square and King's Cross. The fourth blast killed 13 people and ripped apart a bus near Tavistock Square.
People remain on edge -- even more so with the release of a video Wednesday showing one of the four suicide bombers warning of more attacks. It was unclear how the video was obtained or how close before the attacks it was made.
``What you have witnessed now is only the beginning of a series of attacks that will continue and increase in strength," said Shehzad Tanweer, 22, whose backpack bomb killed six people and himself aboard a Circle Line subway train near the Aldgate station in east London.
The bombers -- Tanweer, Mohammed Sidique Khan, 30, Hasib Hussain, 18, and Jamaican-born Germaine Lindsay, 19 -- all grew up in the Leeds area, an ethnically mixed region 200 miles from London.
In a separate video released yesterday, the deputy leader of Al Qaeda asserted that two of the four suicide bombers had spent time at an Al Qaeda camp to prepare for a attack. Ayman al-Zawahri said Tanweer and Khan had come to the camp.