The nation marked the eight anniversary of the Sept. 11 terrorist attacks by honoring the spirit of those who rushed forward to help, from sifting through the fiery rubble at ground zero to sending supplies from thousands of miles away.
Friday was the first time the anniversary was observed as a national day of service, following an order signed this year by President Barack Obama.
"From this day forward, we will safeguard the memories of those who died by rekindling the spirit of service that lit our city with hope and helped keep us strong," said New York Mayor Michael Bloomberg said at a ceremony in lower Manhattan.
Drawing on the spirit that spurred volunteers to rush to the burning towers on Sept. 11, 2001, Americans looked for ways to help each other on a day better known for mourning.
Teresa Mathai, whose husband, Joseph Mathai, died at the World Trade Center eight years ago Friday, planned to grieve at a morning wreath-laying ceremony in Boston and hear his name read out loud. Then she planned to install drywall at a home in south Boston with Habitat for Humanity, one of thousands of volunteer efforts planned since Sept. 11 was declared a national day of service.
"Everyone has a different way of mourning," she said. "Some people keep it absolutely sacred. For me, this is something that gives us solace."
The combination of mourning and national giving was troubling to some who feared the volunteerism would overshadow a somber day to remember the four hijacked jetliners that crashed into the twin towers, the Pentagon and a Pennsylvania field, killing nearly 3,000 people, most in New York.
"When I first heard about it, I was concerned," said Debra Burlingame, whose brother was the pilot of the American Airlines jet that crashed into the Pentagon. "I fear, I greatly fear, at some point we'll transition to turning it into Earth Day where we go and plant trees and the remembrance part will become smaller and smaller and smaller."
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Across the country, a fundraiser to repair storm damage at Central Park, beach cleanups and repairs of homeless shelters were among the organized efforts to give back.
observed a moment of silence in honor of 9/11 victims outside the White House as a single bugler played taps. A Washington rain came to a stop as the observance began at 8:46 a.m., the moment the first jetliner struck the World Trade Center on Sept. 11, 2001. About 150 White House staffers stood in silence around the Obamas.
At a plaza adjacent to ground zero in New York City, families gathered under a cold and steady rain while the names of the Trade Center victims were read, pausing for moments of silence at the minutes the jetliners crashed into the towers.
People involved in volunteer work across the nation joined relatives of victims to read the names of those lost in the twin towers.
One reader represented a group called New York Says Thank You, which sends volunteers from New York City each year on the attacks anniversary to help rebuild communities around the country affected by disasters as a way to send thanks for the help that came to New York City after Sept. 11.
Other readers were from well-known service organizations including the American Red Cross and the United Way.
Thousands were expected Friday at ceremonies at the Pentagon and the crash site of United Airlines Flight 93 in Shanksville, Pa.
In New York City, Vice President Joe Biden spoke during a pause in the reading of the names, telling the several hundred victims' relatives gathered that "there's a special fraternity for those of us who've lost spouses and children." Biden's daughter and first wife died in a 1972 automobile accident.
Before he spoke, Biden joined families who were laying flowers in a reflecting pool on the site where the towers once stood.
Relatives and friends of victims were allowed on Friday to visit the plaza for the Sept. 11 memorial that is under construction. It is expected to be partially complete and open for the 10th anniversary.
Former President George W. Bush had no public appearances planned Friday, and a spokesman said he would be working in his office during the morning. In a brief statement, he said he and his wife, Laura, were thinking of the victims and their families.
"We honor those who volunteer to keep us safe and extend the reach of freedom - including members of the armed forces, law enforcement officers, and intelligence and homeland security professionals," the statement said. "Their courage, service, and sacrifice is a fitting tribute to all those who gave their lives on Sept. 11, 2001. On this day, let us renew our determination to prevent evil from returning to our shores."