Joe Biden, Kamala Harris and George W Bush join mourners in ceremonies in New York, Pennsylvania and at Pentagon
Some wept. Some held photos of loved ones At 8.46am, precisely two decades after a passenger plane became a new and deadly weapon here, all fell silent in remembrance.
Families of the victims gathered at the 9/11 memorial plaza in New York on Saturday to mark the 20th anniversary of terrorist attacks that killed nearly 3,000 people and helped shape the 21st century. Similar ceremonies played out in Washington DC and Pennsylvania – the sites of other attacks that day.