Thousands of people on Saturday attended the New York memorial service marking the 20th anniversary since the Sept. 11 attacks.
Many of them held signs with photos of family members who were killed in the World Trade Center buildings.
"WE WILL NEVER FORGET" read at least one such sign.
At 8:46 a.m., exactly two decades go, five hijackers took control of American Airlines Flight 11 and plunged it into the North Tower above its 90th floor, starting the horrors that would kill almost 3,000 in New York City, the Pentagon, and in a field outside of Shanksville, Pa.
At the same time in New York, 20 years later, the large crowd of people bowed their heads and observed a moment of silence.
"These 20 years have felt like both a long time and a short time, and as we recite the names of those we lost, my memory goes back to that terrible day," Mike Low, whose daughter Sara was a flight attendant on Flight 11, said before the reading of the names. "Today, this is a quiet place of memory."
Family members of the attacks' victims, police officers, firefighters, officials including both President Biden and former Presidents Barack Obama and Bill Clinton, and many others gathered at the Ground Zero memorial, now a plaza and museum honoring those who lost their lives in the coordinated terror attacks.
Biden also traveled to wreath-laying services at the Pentagon and in Shanksville, where former President George W. Bush spoke earlier in the day. The three sites are just a small handful of memorials held across the U.S. to commemorate the lives lost in the attacks, which include many first responders who rushed into the burning towers.
"Twenty years ago, we all found in different ways, in different places, but all at the same moment, that our lives would be changed forever," Bush said at the Flight 93 National Memorial, which marks the location of where the flight crashed after passengers and crew attempted to wrestle back control of the plane from hijackers. All 44 people on board, including the hijackers, were killed.
"The world was loud with carnage and sirens, and then quiet with missing voices that would never be heard again," Bush continued. "These lives remain precious to our country and infinitely precious to many of you. Today we remember your loss, we share your sorrow, and we honor the men and women you have loved so long and so well."
Biden did not speak at the Ground Zero service, but he released a video overnight to mark the occasion. He noted that he has a close friend from Delaware who lost his son in the South Tower.
"To the families of the 2,977 people, from more than 90 nations, killed on Sept. 11, 2001, in New York City, Arlington, Va., and Shanksville, Pa., and the thousand more who were injured, America and the world commemorate you and your loved ones, the pieces of your soul," Biden said.
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He added: "We honor all of those who risked and gave their lives in the minutes, hours, months and years afterwards. The firefighters, the police officers, EMTs, and construction workers, and doctors, and nurses, and faith leaders, service members, veterans — all of the everyday people who gave their all to rescue, recover and rebuild. But it's so hard, whether it's the first year or the 20th. Children are growing up without parents. Parents have suffered without children. Husbands and wives have had to find ways forward without the partners in their lives.
“No matter how much time has passed, these commemorations bring everything painfully back as if you just got the news a few seconds ago. So on this day, Jill and I hold you close in our hearts and send you our love."