A child wearing a firefighter's uniform stands at the reflecting pool in ground zero during the the eighth anniversary commemoration ceremony of the Sept. 11, 2001 terrorists attack. (AP Photo/Chip East, Pool)
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A mourner kneels at the reflecting pool in ground zero during the the eighth anniversary commemoration ceremony of the Sept. 11, 2001 terrorists attack, in New York, Friday Sept. 11, 2009. (AP Photo/Chip East, Pool)
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A member of the Army Band plays a solemn melody on his rain-splatterd trombone during a Sept. 11 anniversary ceremony at the Pentagon, Friday, Sept. 11, 2009. (AP Photo/J. Scott Applewhite)
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Angels representing those who died on United Flight 93 are seen at the temporary memorial site, Friday, Sept. 11, 2009, in Shanksville, Pa. (AP Photo/Carolyn Kaster)
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Wells Morrison with the FBI rings the large bell during the ceremony near the temporary memorial and crash site of United Flight 93, Friday, Sept. 11, 2009, in Shanksville, Pa. (AP Photo/Carolyn Kaster)
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A man waves the American flag as friends and relatives of the victims of the Sept. 11, 2001 attacks gather for a commemoration ceremony at Zuccotti Park, adjacent to ground zero. (AP Photo/Jason DeCrow)
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Teace Snyder, of Scarsdale, N.Y. demonstrates outside the commemoration ceremony on the eighth anniversary of the terrorist attacks, Friday, Sept. 11, 2009, in New York. (AP Photo/Mary Altaffer)
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U.S. military personnel hold their weapons and a US flag during a ceremony to mark the anniversary of Sept. 11 2001, at the main U.S. base, in Bagram. (AP Photo/Musadeq Sadeq)
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Visitors to the temporary memorial for United Flight 93, hold a commemorative flag during a ceremony, Friday, Sept. 11, 2009, in Shanksville, Pa. (AP Photo/Carolyn Kaster)
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A family member of Christopher S. Epps, a victim of Sept. 11, 2001 attack at the World Trade Center, touches a photo of him at the reflecting pool in ground zero. (AP Photo/Chang W. Lee, Pool)
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President Barack Obama places a wreath during a rain-soaked ceremony at the Pentagon, Friday, Sept. 11, 2009. (AP Photo/J. Scott Applewhite)
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Marta Waisman holds a picture of her daughter Gabriela Waisman as family members of victims stand in the rain to pay their respects during a ceremony at the World Trade Center. (AP Photo/Chris Hondros, Pool)
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The World Trade Center flag is folded after being presented as friends and relatives of the victims of the Sept. 11, 2001 attacks gather for a commemoration ceremony at Zuccotti Park. (AP Photo/Jason DeCrow)
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People file past the reflecting pool in ground zero during the the eighth anniversary commemoration ceremony of the Sept. 11, 2001 World Trade Center attack, in New York, Friday Sept. 11, 2009. (AP Photo/Chip East, Pool)
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President Barack Obama and first lady Michelle Obama stand with White House staff members as they participate in a moment of silence marking the eighth anniversary of the Sept. 11 attacks. (AP Photo/Charles Dharapak)
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A firefighter and a police officer from New York hold an American flag as they pay their respects during a ceremony at the World Trade Center. (AP Photo/Chris Hondros, Pool)
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A woman is comforted as friends and relatives of the victims of the Sept. 11, 2001 attacks gather for a commemoration ceremony at Zuccotti Park Friday, Sept. 11, 2009 in New York. (AP Photo/Jason DeCrow)
Copyright 2009 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.