NEW YORK (AP) -- Nine-Eleven observances are under way.
Thousands of people in New York are remembering victims in a park just south of what was once the World Trade Center. Authorities moved the ceremony off the original site this year because of construction work in the pit where four towers will eventually replace the World Trade Center.
The city is allowing family members to briefly go down below street level to lay flowers at a spot near the Twin Towers' footprints. Officials agreed after families threatened to boycott the memorial ceremony.
President Bush is in Washington to mark the moment. He has led a moment of silence on the South Lawn of the White House.
In Shanksville, Pennsylvania, officials are holding a brief but solemn ceremony. Bells will toll and the names of the 40 passengers and crew who died there will be read.
Nation marks six years since terror attacks
Presidential politics loom over this September 11th more than any other anniversary of the attacks.
Firefighters in New York are sharing the podium with former mayor Rudy Giuliani, who many victims' families and firefighters say should not speak this year because he is running for president.
Democratic Senator Hillary Rodham Clinton, who is seeking her party's presidential nomination, also plans to attend ceremonies in New York.
For the first time this year, a victim who did not die at the trade center is being recognized. The city has added the name of an attorney who died of lung disease five months after the attacks to its official list of victims.