Hundreds of people have gathered in Oklahoma City to remember the 168 victims of the bombing 10 years ago.
Tears were shed for those who lost their lives 10 years ago
A moment of silence was held for each of the victims of the attack that destroyed the Alfred P Murrah federal building on 19 April 1995.
Ex-President Bill Clinton, in office at the time, and current Vice-President Dick Cheney paid tribute to the way people had dealt with the tragedy.
Timothy McVeigh was executed for the attack on 11 June 2001.
Co-conspirator Terry Nichols was sentenced to life in prison without parole last year.
The mourners gathered at the Oklahoma City National Memorial - where 168 empty bronze chairs stand on the site of the attack - for the anniversary.
'Test of faith'
Bill Clinton told them that "by the grace of God, time takes its toll not only on youth and beauty, but also on tragedy".
"The tomorrows come almost against our will. And they bring healing and hope, new responsibilities and new possibilities," he added.
Children and infants were among those killed in the attack
Vice-President Cheney said:
"Goodness overcame evil that day.
"All humanity can see you experienced bottomless cruelty and responded with heroism. Your strength was challenged and you held firm. Your faith was tested and it has not wavered."
Among the mourners was survivor Amy Petty.
"Eighteen of my 33 co-workers were killed and I miss them dearly. That doesn't mean that I need to stop living my life. I've got to live," she told ABC News.
"It's good that Oklahoma remembers," said Gail Batiste, aunt of LaKesha Levy, a 21-year-old who had entered the building that morning to get a Social Security card.
The attack was the worst act of domestic terrorism in US history and brought to the attention of the American people the world of radical rightwing paramilitary groups and their followers.