Moment of silence for Boston bombing victims
22 April 2013 Last updated at 19:31 BST
Boston is observing a moment of silence exactly one week after two bombs exploded at the city's marathon, killing three people.
Meanwhile the US Department of Justice says the surviving suspect in the Boston Marathon bombings has been charged with using a weapon of mass destruction.
Dzhokhar Tsarnaev could face the death penalty under the charges.