The FBI is investigating a white South Carolina couple for racial discrimination after they set a cross on fire in their yard last month facing toward their Black neighbors’ home.

Federal civil rights investigators searched the white couple’s home in Conway on Wednesday, according to FBI spokesperson Kevin Wheeler. The retired Black couple also recorded video of the cross being burned on Thanksgiving weekend and described days of repeated threats from their neighbors. The next week, Worden Evander Butler, 28, and Alexis Paige Hartnett, 27, were arrested on state charges of harassment and later released on bond.

Cross burnings in the U.S. are “symbols of hate” that are “inextricably intertwined with the history of the Ku Klux Klan,” according to a 2003 U.S. Supreme Court decision written by the late Justice Sandra Day O’Connor. The justices ruled that the First Amendment allows bans on cross burnings only when they are intended to intimidate because the action “is a particularly virulent form of intimidation.”

The cross wasn’t on fire by the time local police officers arrived, but was still “facing and in full view of the victims’ home,” according to a Horry County Police Department report. Shawn and Monica Williams, the Black neighbors, told WMBF-TV that the burning cross was about 8 feet (2.4 meters) from their fence. They said they’re reconsidering their decision to move to the neighborhood two years ago in light of this experience.