The day that changed America: Remembering 9/11, 20 years on
A rose is left in remembrance of those killed in the September 11, 2001, terrorist attacks, as Americans held memorial observances at the site of the World Trade Center in New York.
Agence France-Presse is an international news agency headquartered in Paris, France.
What you need to know:
On the morning of Tuesday, September 11, 2001, New Yorkers woke to crisp blue skies following a storm that had soaked America's northeastern seaboard the day before.
