The Tribute in Light is illuminated next to the Statue of Liberty during events marking the 11th anniversary of the 9/11 attacks. – Photo by AP

One World Trade Center now up to 104 floors rises above the National September 11 Memorial and Museum. – Photo by AP

One World Trade Center along with surrounding buildings is reflected in the glass facade of the National September 11 Museum in New York. – Photo by AP

Roses and a U.S. flag are laid amid the names of the first responders along the South Pool of the 9/11 Memorial. – Photo by Reuters

Defense Secretary Leon Panetta lays a wreath at the Flight 93 National Memorial during ceremonies commemorating the 11th anniversary of the 9/11 attacks. – Photo by AP

Firefighter John Manning delivers a wreath to Engine Company 10 across from Ground Zero. – Photo by AFP

Zoe Koosoulis and her daughter Eleni help to paint a paint-by-numbers painting of the skyline of lower Manhattan before the terrorist attacks brought down the World Trade. – Photo by AFP

This piece of artwork is called “The Feathers of the Phoenix” and was created by 300 children who lost their parents or siblings in the 9/11 attacks. – Photo by AP

Germano Riviera walks with the "Flag of Honor," which displays the names of all of the victims of the September 11 terrorist attacks, across Ground Zero. – Photo by AFP

People gather at the firefighter’s memorial wall across from Ground Zero. – Photo by AFP

Photos of victims of the attacks of September 11 and messages from their loved ones are displayed along with the faces and recorded voices of those who died as part of the future 9/11 Memorial Museum. – Photo by AP

Defense Secretary Leon Panetta and Patrick White a representative of victim's families visit the crash site. – Photo by AP

Children sit amongst US national flags erected by students and staff from Pepperdine University to honour victims of the 9/11 attacks. – Photo by AFP