US President Joe Biden on Sunday paid tribute to the victims of the 9/11 terror attack by al-Qaeda terrorists, taking part in a remembrance event at the Pentagon, and delivered remarks to honour those killed.
"I know for all those of you who lost someone, 21 years is both a lifetime and no time at all," Biden said at the National 9/11 Pentagon Memorial in Arlington, Virginia.
"It's good to remember. These memories help us heal, but they can also open up the hurt and take us back to that moment when the grief was so raw."