The local Republican Party headquarters in Orange County, North Carolina, was struck overnight with a flammable material thrown through a front window of the building, local authorities said in a statement on Sunday.
Someone also spray-painted graffiti including a swastika and the words "Nazi Republicans leave town or else" on an adjacent building, the town of Hillsborough said on its website.
"The flammable substance appears to have ignited inside the building, burned some furniture and damaged the building’s interior before going out," the statement said. No damage estimates were yet available.The Charlotte Observer
quoted a Republican official as referring to the attack as an act of "political terrorism."
Orange County, where the incident occurred, is overwhelmingly Democratic, according to the Observer
Democratic presidential nominee Hillary Clinton called the attack "horrific and unacceptable."
Republican presidential nominee Donald Trump accused Democrats of being behind the attack, writing on Twitter, "Animals representing Hillary Clinton and Dems in North Carolina just firebombed our office in Orange County because we are winning."