The nation observed the third anniversary of the September 11 terrorist attacks on the United States, which took almost 3,000 lives. Americans paid tribute to the fallen in ceremonies and moments of silence across the country.

Church bells tolled throughout New York at 8:46 a.m., the exact moment the first hijacked plane struck the North Tower of the World Trade Center, as a moment of silence was observed throughout New York State. In Washington, President Bush observed a moment of silence on the White House lawn after attending a prayer service.

At Ground Zero, where the World Trade Center towers once stood, parents and grandparents of the victims read the names of the almost 2,800 people who died there. The two previous ceremonies focused on the children and other relatives of the victims and dignitaries.

New York City Mayor Michael Bloomberg saluted the parents and grandparents as he opened the ceremony.

"Today again we meet in great sadness," Mayor Bloomberg said. "We come here to remember and to ask the country and the world to remember the names of those we lost three years ago. We will never forget that each person was someone's son or daughter."

As the names were read, family members descended a ramp to the floor of Ground Zero, which is now a major construction site. They placed flowers in a reflecting pool set up for the ceremony. The readings paused three more times to observe the times when the second of the Twin Towers was hit and the moments when the buildings collapsed.

Trumpeters from the New York fire and police departments concluded the moving ceremony by playing Taps. For the families of the victims this third commemoration is likely to be the last that will be held in the pit of the site because of the rebuilding effort.

Outside Washington, a wreath laying ceremony at Arlington National Cemetery honored the 184 people who died when a third plane smashed into the Pentagon. Secretary of Defense Donald Rumsfeld spoke to the families gathered there.

"The lives that were lost on September 11 have meaning," he said. "They live on as a testament to a country that is courageous, that is determined, to a people that are resilient despite great loss, and to a cause that continues until that mission is accomplished and beyond."

Bells also tolled across the state of Pennsylvania where 40 airline passengers and crew members died as they took control of a fourth hijacked plane and crashed it to the ground.