As authorities investigated the weekend firebombing of a Republican Party office in North Carolina, supporters from across the political spectrum rallied behind the victims.
That included a Democratic tech writer in Boston who started a GoFundMe page to raise money to help the Orange County Republican Party recover from the attack, which destroyed the group's headquarters in Hillsborough but did not injure anyone.
The organizer, David Weinberger, said he and some other Democrats, along with some independents, started the campaign "because we believe that in order for our democracy to survive, we have to work against the violent force that want to disrupt it." By Monday morning the campaign raised more than $13,000 from more than 500 donors.
Who did it, and why, remains a mystery. But the attackers seemed bent on causing a lot of damage — and fear. The fire was caused by a flammable bottle thrown through a window of the office sometime overnight Saturday, authorities said. Outside, someone wrote on an adjacent wall, "Nazi Republicans" and, "Leave town or else," adding a swastika.
The first person to call police was a neighbor, who dialed 911 just before 9 a.m. Sunday to report smoke coming from the building. By then, the fire had burned out, and the damage was done.
"They obviously threw something that was flaming through the window of the Republican Party," the neighbor said, according to 911 tapes released Monday.
Federal agents are helping local authorities investigate. They believe the bombing happened sometime after midnight Sunday. The head of the North Carolina GOP called the bombing a hate crime and a "violent attack against our country." He asked that all local Republican offices close at sundown.
Terrorism researchers said that the overtly political nature of the target, and the damage the bomb caused, appeared to meet their criteria for terrorism. But they also said it was unlikely that any suspect would be charged with terrorism, because criminal statutes use more stringent definitions, including the attacker's intent, and can be more difficult to prove.
"It appears to be an ideologically motivated act of violence, so that might fall under some definitions of terrorism," said Charles Kurzman, a professor of sociology at the University of North Carolina at Chapel Hill.
The researchers also noted that the firebombing of a political office is rare these days, particularly in comparison to the 1960s and 1970s, when such attacks — often committed by left-wing groups — occurred with higher frequency.
More recently, in 2000, the Earth Liberation Front started a fire at the Monroe County Republican Party headquarters in Bloomington, Indiana, causing minor damage, according to the Global Terrorism Database, maintained by the National Consortium for the Study of Terrorism and Responses to Terrorism at the University of Maryland.
Two years ago, an anti-government extremist threw Molotov cocktails at the empty office of U.S. Rep. Emanuel Cleaver in Kansas City, according to the database.
Gary LaFree, the consortium's director, said the attack in North Carolina would likely be added to the list.
North Carolina Republican Party spokeswoman Emily Weeks told NBC News that the Orange County Republican Party office is totally unusable and that materials inside may have been destroyed. The state party said Monday that completed absentee ballots were not stored at that office.
Republican presidential nominee Donald Trump blamed — without proof — "animals representing Hillary Clinton and Dems in North Carolina."
Clinton condemned the attack as "horrific and unacceptable."
CORRECTION: A previous version of this article quoted a party official as saying completed absentee ballots might have been destroyed in the attack on the Orange County Republican Party office, which was incorrect. The North Carolina Republican Party and its county organizations do not collect completed absentee ballots.