Atlanta, June 20 (RHC)-- Nearly 20 known hate groups currently operate in the US state of South Carolina, where a white gunman killed 9 African Americans at a historic black church on Wednesday, according to civil rights advocacy organization.

South Carolina is home to 19 known hate groups, including two factions of the Ku Klux Klan and four "white nationalist" organizations, NBC News reports, citing the Southern Poverty Law Center.

More than a dozen of the groups listed are explicitly based on racial hatred, the Southern Poverty Law Center said. Two branches of the League of the South, which advocates for Southern U.S. states to secede from the country and "the advancement of Anglo-Celtic culture, are also located in South Carolina.

Its website states: "If you call us racists, our response will be 'So what?'"

Among the “white nationalist” groups active in the state is the Council of Conservative Citizens, which is opposed to racial integration and “similar measures to destroy or denigrate the European-American heritage, including the heritage of the Southern people."

Other racist groups listed by the civil rights group include three neo-Nazi cells, a chapter of the white supremacy movement Confederate Hammerskins and an anti-immigration protest group called Americans Have Had Enough.