"While we do not yet know all of the details, we do know that we'll never understand what motivates anyone to enter one of our places of worship and take the life of another," she wrote in a statement.
Presidential candidates began to weigh in as well.
Hillary Clinton was in town already for a fundraiser, but one of her Republican rivals, Jeb Bush, announced he would be canceling an event in the city that had been previously scheduled for today.
Celebrities also took to Twitter to share their condolences and messages with the survivors.
“Charleston” was trending on Twitter overnight and some of the most moving posts came from individuals, whether they had personal connections to the city.
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