Roof, 21, a suspected white supremacist, already had been charged with nine counts of murder and one weapons charge in the killings of nine parishioners at Emanuel African Methodist Episcopal Church. Those charges also were included in the new indictments.
"These attempted murder charges are related to the victims who survived their attack at Mother Emanuel," the local prosecutor, Ninth Circuit Solicitor Scarlett A. Wilson, said in a statement Tuesday, using the church's nickname.
Wilson added that she could not comment further on
"While it is extremely important to me that I am open and transparent with the public about the legal proceedings and the continuing investigation into this matter, as a lawyer and prosecutor, I am subject to special rules limiting my ability to make public comments about pending cases and defendants in criminal matters," Wilson said, noting that Roof is innocent until proven guilty.
The indictment documents do not give any details on the shooting other than that the surviving victims were two women and a girl, whose names were redacted.
Criminal complaints from the previous charges filed against Roof said he entered the church and met with the parishioners at a Bible study for an hour before opening fire.
"Prior to leaving the Bible study room, he stood over a witness to be named later and uttered a racially inflammatory statement to the witness," those documents said.
An online manifesto linked to Roof, discovered after the shooting, espoused white supremacist ideology as well as a call to action.
"We have no skinheads, no real KKK, no one doing anything but talking on the internet," the manifesto said. "Well someone has to have the bravery to take it to the real world, and I guess that has to be me."
Roof was arrested in North Carolina, without incident, the day after the shooting.
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