Then, the American national anthem echoed through cathedrals and schools, shops and stock exchanges, U.S. embassies and military bases.
The organ and congregation thundered The Star-Spangled Banner at St. Paul's Cathedral in London, where Queen Elizabeth II and Prime Minister Tony Blair led more than 2,000 in prayer. Thousands more were turned away by police.
Among the throngs outside, Heather Robinson, an American who lives in England, said she did not know anyone who was killed but felt she had to come to pay her respects.
I can't even go home now, she said, sobbing on the shoulder of her English husband. I feel very helpless.
Tariq Muhammad Dhamial, a native of Pakistan, stood out in traditional Sunni Muslim black garb, a green head band and long beard. I am here to show as a Muslim that we condemn these acts, he said.
Most European nations observed a three-minute silence at noon as floral bouquets swelled outside American embassies. One exception was Serbia, the dominant republic of Yugoslavia, where authorities called no period of mourning. The smaller Yugoslav republic of Montenegro did declare a day of mourning.
In Italy, Pope John Paul II joined the mourning. The Vatican said that at noon the 81-year-old Pope went to his private chapel in the papal summer residence at Castelgandolfo, south of Rome.
He retreated into silent prayer for the victims of the terror attacks that struck the United States last Tuesday and to implore comfort for the injured and for reconciliation and peace in the world, spokesman Joaquin Navarro-Valls said.
From Germany to Greece, television stations switched to religious ceremonies or broadcast black screens. In Paris, French President Jacques Chirac stood to attention in front of a military honor guard at the Elysee Palace, where the Republican Guard also played The Star-Spangled Banner.
The global day of grief began in Asia, where sirens blared for one minute in South Korea and young children appeared outside the American Embassy in Seoul. Some knelt before the building, closed their eyes and prayed silently, alongside a few adults accompanying them. Others placed flowers to honor the unknown thousands who died in Tuesday's suicide attacks on the World Trade Center and the Pentagon.
The somber mood ran particularly deep on American military bases and naval vessels abroad, whose personnel wondered when they might be ordered to strike back.
It has been a rollercoaster of emotion over the last few days, from the initial shock and horror of the event to the more somber mood which you see today, said Air Force Col. John Brennan, commander of Lakenheath air base south of London, where 15,000 service personnel and families make it the biggest American base in Europe.
Now w have to get back to work, said Brennan after services capped by a wailing rendition of Amazing Grace by a lone bagpiper. We have to resume our training and focus on our combat readiness and we are ready to go.
In Europe, stock exchanges from Norway to Austria stopped business for three minutes, and other lives paused in the most trivial of ways. In Britain, lottery ticket sales halted in convenience stores, and pubs delayed their usual 11 a.m. opening. In Finland, cabbies pulled to the side of the road. In Iceland, fishermen stood in silence at the Reykjavik docks.
In Ireland, the government ordered most offices and businesses to close for the entire day.
At St. Mary's Catholic Cathedral in Dublin, plaintive harps and violins accompanied messages from Catholic and Protestant leaders together.
Ireland is broken-hearted and grieving deeply at the unconscionable waste of life which we have witnessed this week, said President Mary McAleese, who led the congregration in prayers for world leaders to show wisdom so that justice and mercy may prevail in our world.
Many American embassies, including those in Denmark and India, created places on their Web sites for electronic condolences. Hand-written condolence books continued to fill up in parliaments and city halls across continents.
In Singapore, Americans and Singaporeans placed flowers and tributes outside the fortress-like U.S. embassy in the city-state. Each hour, officials emerged from the building to clear away the offerings so the wrappings and packages could be searched for safety reasons.
In Hungary, firefighters tied black ribbons on their vehicles in sympathy and solidarity with the American firefighters who lost comrades when the World Trade Center's twin towers collapsed.
Amid the mourning came pleas that anger not be vented on the innocent, particularly in countries with substantial Muslim minorities.
In Indonesia, the world's most populous Muslim country, sympathy for America mixed with worried predictions about its government's response.
We are very concerned with the fact that so many civilians died in Tuesday's attack, said Hasbullah Mursyid, a cleric at Jakarta's main Istiqlal Mosque, the biggest in Southeast Asia.
However, U.S. authorities should not stereotype all Muslims or Arabs, and treat them as scapegoats, Mursyid said in a sermon to several thousand people packing the mosque.
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