Carolina shooting revives memories of US 'dark history'
President Barack Obama has said that the shooting of nine people in Charleston has revived memories of what he called "a dark part of US history".
For many, the attack reminded them of the bombing of the African-American 16th Street Baptist Church in Birmingham, Alabama, in 1963, by four members of the Ku Klux Klan.
The attack in Charleston has opened up historic wounds. Nick Bryant reports.