A US flag is carried through the fields at the Flight 93 National Memorial in Shanksville, Pennsylvania, before a luminaria service on September 10. The service was held to mark the 15th anniversary of American Airlines Flight 93 crashing into a field outside Shanksville with 40 passengers and four hijackers aboard, along with attacks on the World Trade Center and the Pentagon, on September 11, 2001.
A US flag is carried through the fields at the Flight 93 National Memorial in Shanksville, Pennsylvania, before a luminaria service on September 10. The service was held to mark the 15th anniversary of American Airlines Flight 93 crashing into a field outside Shanksville with 40 passengers and four hijackers aboard, along with attacks on the World Trade Center and the Pentagon, on September 11, 2001.
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Pennsylvania National Guard Private Edward Noon, 22, says a prayer during a luminaria service at the Flight 93 National Memorial on September 10 in Shanksville, Pennsylvania.
Pennsylvania National Guard Private Edward Noon, 22, says a prayer during a luminaria service at the Flight 93 National Memorial on September 10 in Shanksville, Pennsylvania.
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The sun rises over the Pentagon on Sunday prior to a morning ceremony to commemorate the 15th anniversary of the September 11, 2001 terror attacks. The Pentagon Memorial commemorates the 184 lives lost at the Pentagon and onboard American Airlines Flight 77 that day.
The sun rises over the Pentagon on Sunday prior to a morning ceremony to commemorate the 15th anniversary of the September 11, 2001 terror attacks. The Pentagon Memorial commemorates the 184 lives lost at the Pentagon and onboard American Airlines Flight 77 that day.
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A firefighter rings a bell as family members, emergency workers and others attend a commemoration ceremony for the victims of the September 11 terrorist attacks at the National September 11 Memorial and Museum on Sunday in New York City.
A firefighter rings a bell as family members, emergency workers and others attend a commemoration ceremony for the victims of the September 11 terrorist attacks at the National September 11 Memorial and Museum on Sunday in New York City.
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An American flag stands among names on the 9/11 memorial before the start of the 15th anniversary memorial service to 9/11 victims in New York.
An American flag stands among names on the 9/11 memorial before the start of the 15th anniversary memorial service to 9/11 victims in New York.
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A woman hugs a man during a commemoration ceremony for the victims of the September 11 terrorist attacks in New York.
A woman hugs a man during a commemoration ceremony for the victims of the September 11 terrorist attacks in New York.
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A group of motorcycle riders look over the north memorial pool Sunday during services marking the 15th anniversary of September 11 at the 9/11 Memorial and Museum in New York.
A group of motorcycle riders look over the north memorial pool Sunday during services marking the 15th anniversary of September 11 at the 9/11 Memorial and Museum in New York.
BRYAN R. SMITH/AFP/Getty Images
A man honors a lost loved one at a commemoration ceremony for the victims of the September 11 terrorist attacks in New York City.
A man honors a lost loved one at a commemoration ceremony for the victims of the September 11 terrorist attacks in New York City.
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A girl cries while reading the names of the victims during a ceremony Sunday marking the 15th anniversary of September 11 attacks at the National 9/11 Memorial in New York.
A girl cries while reading the names of the victims during a ceremony Sunday marking the 15th anniversary of September 11 attacks at the National 9/11 Memorial in New York.
Xinhua/Sipa USA
An Army service member salutes during the a ceremony remembering the victims of the September 11 terrorist attacks at the National September 11 Memorial and Museum.
An Army service member salutes during the a ceremony remembering the victims of the September 11 terrorist attacks at the National September 11 Memorial and Museum.
Spencer Platt/Getty Images
Family members embrace Sunday during the 15th-anniversary service at the 9/11 Memorial and Museum.
Family members embrace Sunday during the 15th-anniversary service at the 9/11 Memorial and Museum.
BRYAN R. SMITH/AFP/Getty Images
US military personnel attend a memorial ceremony on the 15th anniversary of the September 11, 2001 attacks at the International Security Assistance Force headquarters in Kabul, Afghanistan.
US military personnel attend a memorial ceremony on the 15th anniversary of the September 11, 2001 attacks at the International Security Assistance Force headquarters in Kabul, Afghanistan.
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Attendees hold photographs of loved ones lost in the September 11 terrorist attacks at a commemoration ceremony Sunday at the National September 11 Memorial and Museum in New York.
Attendees hold photographs of loved ones lost in the September 11 terrorist attacks at a commemoration ceremony Sunday at the National September 11 Memorial and Museum in New York.
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United Airlines flight attendants Clarice Rinker and Janeen Brown embrace by the Wall of Names at the Flight 93 National Memorial near Shanksville, Pennsylvania, on the 15th anniversary of the terror attacks. Their fellow flight attendants and pilots were killed when Flight 93 crashed in a field near Shanksville.
United Airlines flight attendants Clarice Rinker and Janeen Brown embrace by the Wall of Names at the Flight 93 National Memorial near Shanksville, Pennsylvania, on the 15th anniversary of the terror attacks. Their fellow flight attendants and pilots were killed when Flight 93 crashed in a field near Shanksville.
John Rucosky/Tribune-Democrat/AP
Military personnel salute during a ceremony Sunday to mark the 15th anniversary of the 9/11 attacks at the Pentagon Memorial in Washington, DC.
Military personnel salute during a ceremony Sunday to mark the 15th anniversary of the 9/11 attacks at the Pentagon Memorial in Washington, DC.
JOSE LUIS MAGANA/AFP/Getty Images
People attending Sunday's ceremony at the Pentagon.
People attending Sunday's ceremony at the Pentagon.
NICHOLAS KAMM/AFP/Getty Images
President Barack Obama lays a wreath during a ceremony Sunday at the Pentagon Memorial to mark the 15th anniversary of the 9/11 terrorist attacks.
President Barack Obama lays a wreath during a ceremony Sunday at the Pentagon Memorial to mark the 15th anniversary of the 9/11 terrorist attacks.
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Visitors view the sunset from the observatory of One World Trade Center on Sunday, September 11, the 15th anniversary of the 2001 attacks.
Visitors view the sunset from the observatory of One World Trade Center on Sunday, September 11, the 15th anniversary of the 2001 attacks.
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The "Tribute in Light" beams from the skyline of Lower Manhattan where the Twin Towers once stood, as seen from the Brooklyn Heights Promenade on September 11 in New York City. The tribute light commemorates 2,977 people who were killed in New York, at the Pentagon and in Pennsylvania on September 11, 2001.
The "Tribute in Light" beams from the skyline of Lower Manhattan where the Twin Towers once stood, as seen from the Brooklyn Heights Promenade on September 11 in New York City. The tribute light commemorates 2,977 people who were killed in New York, at the Pentagon and in Pennsylvania on September 11, 2001.
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