The Ku Klux Klan plans to hold a pro-Confederate flag rally at the South Carolina Capitol, where a statue of a former state governor who championed white supremacy was vandalized on Tuesday amid scrutiny of symbols associated with slavery.
The Civil War-era flag and related monuments have become flashpoints after a shooting killed nine people at a historic black church in Charleston, South Carolina.
The suspected shooter, Dylann Roof, a 21-year-old white man, had posed with a Confederate flag in photos posted on a website that displayed a racist manifesto attributed to him.
The June 17 shootings triggered calls for South Carolina to remove the Confederate flag on State House grounds in Columbia.
The massacre followed a year of debate over US race relations spurred by the killings of unarmed black men by police in Missouri and New York City, and the case of a black man in Baltimore who died of injuries suffered in police custody.
The Loyal White Knights chapter of the Ku Klux Klan, based in North Carolina, said it will rally at the South Carolina State House on July 18.
"We're standing up for the Confederacy," James Spears, who holds the title "great titan" for the group, said on Tuesday.
He said speakers would address slavery, then the Klan will hold a ceremonial cross-lighting ceremony on private property. South Carolina governor Nikki Haley, a Republican who has called for the flag's removal, said the group was not welcome in the state.
The Ku Klux Klan, a white supremacist group, is known for its history of violence and intimidation against African-Americans. On Tuesday, a statue of segregationist governor and US Senator Ben Tillman, who held office in the late 19th and early 20th centuries, was defaced with what appeared to be red paint, authorities said.
The vandalism followed the arrest Monday night of a man confronting anti-flag protesters at the State House. Nicholas Thompson, 25, of South Carolina was charged with disorderly conduct, police said.
About 30 people were protesting the flag when 15 vehicles with pro-flag supporters stopped in the street, authorities said.
As the debate extends across the US South, Baltimore mayor Stephanie Rawlings-Blake said on Tuesday she was appointing a commission to review the Maryland city's Confederate statues and historical items.
In Virginia, the Sons of Confederate Veterans vowed to oppose Democratic Governor Terry McAuliffe's order to remove the flag from state-issued license plates.