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New York illuminates where the Twin Towers once stood in striking September 11 memorial
11 September 2021, 07:11
New York lit up the night sky with a moving memorial to the victims of September 11.
The city's "Tribute in Light" saw the city light up where the Twin Towers once stood.
It came ahead of a day of commemorations to the attacks as Joe Biden pleaded for a "true sense of national unity".
In remarks released by the White House of Friday, the president said the American response to 9/11 saw "heroism everywhere – in places expected and unexpected".
"To me that's the central lesson of September 11," he added.
"Unity is our greatest strength."
Mr Biden was due to spend Saturday visiting all three crash sites from the 2001 attacks, and visited New York to see the light memorial on Friday night.
He is set to travel to the National September 11 Memorial at the former site of the Twin Towers before travelling to Shankville in Pennsylvania.
There, a plane came down after passengers fought its hijackers as they flew towards Washington.
He will then go to the Pentagon, the headquarters of the US Department of Defence and home of the US military, where a plane struck.
"No matter how much time has passed, these commemorations bring everything painfully back as if you just got the news a few seconds ago," Mr Biden said.