It was not immediately clear how many people had been shot, but the Charleston Post and Courier said eight people had been wounded.
The Charleston police department said the suspect is a clean-shaven white man, aged about 21. As of 11:30 pm (0330 GMT), the suspect was still at large.
Local network ABC4 News said police were also investigating a possible bomb threat.
The shooting happened at the Emanuel African Methodist Episcopal Church. According to its website, it is the oldest such church in the US south.
source: interaksyon.com
