By Rhea Mogul and Minyvonne Burke
President Joe Biden and first lady Jill Biden joined a large crowd including victims’ families at the National September 11 Memorial where the twin towers once stood, to observe the first at 8:46 a.m. ET.
That marked the time that Al Qaeda terrorists crashed American Airlines Flight 11 into the north tower of New York’s World Trade Center two decades ago.
They were joined by former Presidents Barack Obama and Bill Clinton as well as several national and state leaders, members of the emergency services and large crowds.
Just 23 minutes later, a second moment of silence was held at the same time that American Airlines Flight 175 hit the south tower.
After both moments, family members read out the names of those killed in the 9/11 attacks and the 1993 World Trade Center bombing. Bruce Springsteen also performed “I’ll See You in My Dreams.”
Meanwhile at the Pentagon, the first of a number of events began shortly before 7 a.m. ET. As the national anthem rang out, a flag was unfurled down the side of the building, which was hit that day.
A third moment of silence was held at 9:37 a.m. ET, to remember those who lost their lives when American Airlines Flight 77 crashed into the Pentagon. Afterward, a rendition of “You’ll Never Walk Alone” was performed for the crowd followed by more names being read of those who died.
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At 9:59 a.m. ET another moment of silence was held to mark when the south tower collapsed.
In Shanksville, Pennsylvania, a moment of silence was held at 10:03 a.m. ET for the heroic passengers who fought terrorists aboard United Airlines Flight 93 and prevented the plane from reaching Washington.
Family members read the names of their loved ones as a bell rang.
Former President George W. Bush, who was reading a book to Florida schoolchildren when the planes hit, is also expected to give a speech in the rural town.
Another moment of silence will also be held at 10:28 a.m. when the neighboring north tower crumbled to the ground.
Vice President Kamala Harris is scheduled to give remarks around 10:45 a.m. ET.
Biden is scheduled to travel to all the attack sites. On Friday, he made an appeal to the nation to reclaim the spirit of cooperation that evolved in the days following 9/11.
In a taped address by the White House, Biden spoke of a “true sense of national unity” that emerged after the attacks, adding that he saw “heroism everywhere — in places expected and unexpected.”
“To me that’s the central lesson of Sept. 11,” he said. “Unity is our greatest strength.”
Biden arrived in New York on Friday night as the skyline was illuminated by the “Tribute in Light,” hauntingly marking where the towers once stood.
He is the fourth president to console the nation on the anniversary of that dark day, one that has shaped many of the most consequential domestic and foreign policy decisions made by the chief executives over the past two decades.
He will conclude official events by laying a wreath at the Pentagon later in the afternoon.