A federal grand jury on Wednesday indicted suspected white supremacist Dylann Roof on hate crime and other charges over the June 17 massacre of nine black parishioners in an African-American church in Charleston, South Carolina.

The indictments, announced in Washington by US Attorney General Loretta Lynch, are in addition to state murder and attempted murder charges against the 21-year-old suspect.

"Racially-motivated violence such as this is the original domestic terrorism," Lynch told reporters.