Police in North Carolina were investigating the apparent firebombing of a county Republican Party office near the state capital, local media reported.

The North Carolina Republican Party said the GOP headquarters in Orange County, about 40 miles northwest of Raleigh, suffered major damage when it was attacked Saturday night. No one was injured during the attack, WCNC-TV reported.

Party officials said an explosive device was thrown through a window of the county headquarters in Hillsborough, N.C. The words “Nazi Republicans, leave town or else” were spray-painted on a nearby building.

Dallas Woodhouse, executive director of the North Carolina Republican Party, denounced the attack, calling it “political terrorism.” He said all Americans “should be outraged by this hate-filled and violent attack against our democracy.”

He said the office was “a total loss.”

“The only thing important to us is that nobody was killed, and they very well could have been,” he told The Charlotte Observer.

Party officials will ask for more security at all offices and events between now and Election Day, Woodhouse said.

In a statement, Hillsborough Mayor Tom Stevens said the “highly disturbing act goes far beyond vandalizing property; it willfully threatens our community’s safety via fire, and its hateful message undermines decency, respect and integrity in civic participation.”

Orange County, home to the University of North Carolina in nearby Chapel Hill, is overwhelmingly Democratic, The Observer reported. Democrats and independents outnumber Republicans 5-1.

N.C. Democratic Party Chair Patsy Keever called the bombing “outrageous.”

“I’m appalled that this would happen, certainly we don’t need violence for any reason,” she said. “Clearly this is outrageous that anybody would do this kind of destruction to either party’s buildings or people.”

And Democratic presidential nominee Hillary Clinton also took to Twitter to denounce the damage.

Follow Greg Toppo on Twitter: @gtoppo