Solemn memorial services in New York, Washington and Pennsylvania began on Friday marking the eighth anniversary of the September 11, 2001, terrorist attacks.
In New York, relatives and friends of those that died read out the names of the nearly 3,000 victims.
In Washington, President Obama, the first lady and White House staff observed a moment of silence at 8:46 a.m., the moment when American Airlines Flight 11 crashed into the north tower of the World Trade Center.
The president is later expected to visit the Pentagon, where he will speak and participate in a wreath-laying ceremony for the 184 victims killed when American Airlines Flight 77 struck the building’s west wall.
In New York, a moment of silence was observed at 9:03 a.m. the time when United Airlines Flight 175 crashed into the tower of the World Trade Center.
In Shanksville, a ceremony will also be held just before 10 a.m. to remember the 40 passengers and crew of United Airlines Flight 93, who died when the hijacked plane went down in a field there.
The following dramatic footage of the moment the second plane crashed into the World Trade Center has recently surfaced.
The video was shot through a chain-link fence and shows black smoke pouring from the North Tower as a hijacked jet smashes into the South Tower.