Charleston, June 18 (RHC)-- U.S. police caught a young, white gunman who opened fire inside an historic Black church in South Carolina, killing nine people and wounding several others. 21-year-old Dylann Roof was arrested Thursday morning about three hours north of the crime scene.

The victims were attending Bible study at the Emanuel African Methodist Episcopal Church when the attack occurred, shortly after 9 p.m. Wednesday evening local time. Charleston Police Chief Gregory Mullen called the massacre a hate crime.

The known victims include the church’s pastor, the Reverend Clementa Pinckney, and his sister. Reverend Pinckney also served as a state senator. Just hours earlier, he had campaigned with Democratic hopeful Hillary Clinton in Charleston.

Known as "Mother Emanuel," the Emanuel AME Church is home to the oldest Black congregation south of the U.S. city of Baltimore. It was burned in the 1820s during a slave rebellion and has stood at its present location since 1872.