Meanwhile, tributes and heartfelt condolences were offered to the United States around the world, which in a reminder of the momentous changes wrought by the attacks, closed a string of embassies and boosted security in response to new terror threats.

At dawn, the American flag was raised and then lowered to half-mast at Bagram Air Base north of the Afghan capital Kabul, where US troops are spearheading the fight against al-Qaeda militants blamed for the carnage one year ago.

The distance from New York's "Ground Zero," where two hijacked aircraft decimated the 110-story twin towers of the World Trade Center, made little difference in the Pacific, where Fijians, New Zealanders and Sydneysiders laid flowers and bowed their heads in silent tribute.

Memorial ceremonies and services were being held across Asia, from Seoul and Singapore to Vietnam, China, the Philippines and Pakistan. Staff at the South Pole's Scott-Amundsen Base also held a service.

Security forces went on special alert across the region, where tensions between Muslims and non-Muslims from Indonesia to India have created some among the world's hottest trouble spots.

A memorial service went ahead amid strict security in a nervous Singapore, while US embassies in Malaysia, Indonesia, Vietnam, Cambodia and Pakistan were shut because of new terrorist threats.

The ravages of war, AIDS and famine in politically and economically marginalized Africa left few tears to spare for the anniversary of the attacks blamed on the al-Qaeda network of Saudi-born millionaire Osama bin Laden.

Any tributes to the victims and the forever-changed United States were to come from US diplomatic missions, two of which -- in Kenya and Tanzania -- were among the first victims of al-Qaeda.

The global Islamic militant network targeted the US embassies in the East African nations in 1998, with the attack in Nairobi claiming 250 lives and leaving more than 5,000 wounded.

President Vladimir Putin sent condolences on behalf of Russia from his holiday residence on the Black Sea early Wednesday morning.

Meanwhile the European Union said it remained "side by side" with the United States as nations across the region prepared for their own tributes to the victims.

From London, Britain's Queen Elizabeth II paid tribute to the "resilience" of New Yorkers in a message read late Tuesday in the Saint Thomas Church in New York during a memorial service.

"We admire these qualities in the strength of the families of the victims" in the determination of the rescue workers" and in the extraordinary spirit and resilience demonstrated by the people of New York," the message released by Buckingham Palace said.

People across Europe are to show solidarity with the United States Wednesday with a wave of concerts, prayers and candlelight vigils, which take on added poignancy amid fears of a war with Iraq.

In New York, the bagpipers continued their solemn march, a team of five -- a flag bearer, two drummers and two pipers -- planning to walk nearly 31 kilometers (19 miles) from the northernmost tip of the Bronx to "Ground Zero," to arrive at 8:46 am (1246 GMT), when the first of two planes to hit the towers struck.

The processions opened a day to be filled with candlelight ceremonies, prayers, speeches and concerts in New York. Cities nationwide were expected to pay homage to those who lost their lives in the strikes.

The nation was on high alert and fighter planes seared the night skies in the quiet hours before Americans woke to pay tribute to the lives lost. Missiles were poised at the ready in Washington, while Vice President Dick Cheney was shuttled to an undisclosed location as a precaution.

Officials on Tuesday said they had increased their terror alert from "elevated" to "high" because of new threats a year after the attacks by Islamic suicide commandos who turned hijacked airliners into flying bombs.

"This heightened threat level has been communicated to local and state authorities, federal agencies and members of Congress," said Homeland Security Chief Tom Ridge.

President George W. Bush was to begin the day in Washington with a private memorial service before laying a wreath at the Pentagon. The field near Shanksville, Pennsylvania, where passengers and crewmembers overpowered hijackers who were bound for a Washington target, authorities believe, was to be his next stop.

He was to cap Wednesday with a speech in New York harbor, the Statue of Liberty lofting behind him as he concluded an emotional day also carrying significant political overtones, as Bush seeks to boost support for his global war on terrorism and a possible pre-emptive strike against Iraqi President Saddam Hussein.

Nampa-AFP

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