The 21-year-old white gunman who slaughtered nine people at a Charleston, South Carolina, church was previously jailed in March on a drug charge, NBC affiliate WIS-TV reported.
He is suspected of gunning down nine people at the historically black Emanuel African Methodist Episcopal Church on Wednesday night while sitting in on a Bible study class. Three others survived.
He was captured by police Thursday morning, sources said.
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Police said Roof fled after the shooting just after 9 p.m. ET in a black Hyundai Elantra.
Charleston officials are investigating the shooting as a hate crime. The Justice Department also announced it is opening a parallel civil rights investigation into the case.








