www.bbc.co.uk/news/world-us-canada-33190735
The killer appears to fit typical sort of mass shooter profile - young, 'loner', male. Apparently he attended an hour's bible study in the black church, before opening fire.
It's not clear if it was a random anti-black hate crime, or if the pastor, one of the dead, a Democratic state senator, was the target. en.wikipedia.org/wiki/Clementa_C._Pinckney
The killer's getaway vehicle bore Confederate flag plates, and he had a jacket with Rhodesia and apartheid-era South Africa flags. time.com/3926593/charleston-killer-flags/