Ceremonies marking the 11th anniversary of the September 11 terror attacks have begun in New York, with a moment of silence held at the time when the first hijacked jet crashed into the World Trade Centre in 2001.
The reading of nearly 3,000 victims' names in New York, Washington and Pennsylvania continued as usual this year.
But many felt it was time to move forward after the emotional turning point of last year's 10th anniversary.
For the first time in New York, only family members were to speak at the anniversary ceremony. Elected officials had spoken in past years.
Jane Pollicino was among the 300 people who gathered at the September 11 memorial, which opened last year. She said there is less pressure during this year than the 10th year anniversary.
Meanwhile, President Barack Obama, first lady Michelle Obama and White House staff observed a moment of silence on the White House lawn.
Vice president Joe Biden was travelling to Pennsylvania to deliver remarks at the Flight 93 National Memorial Commemorative Service.