9/11 anniversary marked

Thousands of people are gathering to mark the eighth anniversary of the Sept. 11 attacks in remembrance ceremonies planned across the United States and internationally.

On Sept. 11, 2001, two hijacked planes crashed into the World Trade Center in New York City, one at the Pentagon in Arlington, Va., and a fourth in a field in Shanksville, Pa. Almost 3,000 people died in the attacks, including 24 Canadians.

Officials have said thousands of people are expected to attend the three annual ceremonies at the crash sites.

Four moments of silence, at 8:46 a.m., 9:03 a.m., 9:59 a.m. and 10:29 a.m. ET, will be held, marking the times when the first and second hijacked planes hit the WTC buildings and when the south and north towers fell.

People carrying photos of victims were streaming into the plaza southwest of Ground Zero for the ceremony on the rainy and windy morning. Construction is now occurring on the footprint site of the World Trade Center for a new tower, an underground museum and a memorial park.

The names of the victims will be read at the ceremony, which will be attended by U.S. vice-president Joe Biden.

Name added

This year, one new name will be read — a victim added to New York's death toll in January. The medical examiner's office ruled that Leon Heyward, who died last year of lymphoma and lung disease, was a homicide victim because he was caught in the toxic dust cloud just after the towers collapsed.

It's the second time the city has added to the victims' list someone who died long after Sept. 11, ruling that exposure to toxic dust caused lung disease.

Many emergency workers died as they tried to rescue victims from the twin towers, while thousands more say they are still suffering from persistent respiratory problems.

President Barack Obama will attend a wreath-laying ceremony at the Pentagon, where 184 people died. In Pennsylvania, the names of victims on United Flight 93 will be read at 10:03 a.m., the time the plane crashed.

A name-reading ceremony is also scheduled in Boston, where two of the planes departed.

In Canada, a service will be held in Appleton, N.L., near Gander where planes were diverted to in 2001. Prime Minister Stephen Harper will be attending a remembrance ceremony at Beechwood cemetery in Ottawa.

Two Canadian warships have also been sent to New York to participate in the American ceremony on Friday.

9.11-kilometre run

In Afghanistan, meanwhile, about 1,000 American troops were participating in a memorial run that spanned 9.11 kilometres at Bagram Air Field.

In Britain, a wreath-laying ceremony was held in Grosvenor Square in London for the 67 British people killed.

Obama and Defence Secretary Robert Gates are scheduled to meet with victims' family members on Friday.

The president will "speak about what the day means and the sacrifices of thousands, not just at the Pentagon, but in Pennsylvania and certainly and most obviously in New York," said White House press secretary Robert Gibbs.

Obama issued a proclamation on Thursday honouring those who died and urging Americans to mark the anniversary with acts of community service. Sept. 11 was declared a national day of service earlier this year.