DURHAM, N.C. (WNCN) — As law enforcement officials investigate the attack on the substations in Moore County, a homeland security expert said Monday it’s too soon to say if it was an act of domestic terrorism — but that it highlights challenges in hardening infrastructure.

Officials in Moore County said that the damage at the substations was caused on Saturday evening by gunfire. No one has claimed responsibility. The incident left more than 40,000 customers without power, potentially for days.

“We just don’t know exactly who the perpetrators are or what their motives are. But, once we do, the label of domestic terrorism could certainly be applied here, but it just depends,” David Schanzer said, the director of the Triangle Center on Terrorism and Homeland Security at Duke University. “Domestic terrorism is defined principally as violence against persons or properties for some sort of political purpose or grievance to try to influence the government in some way.”

Investigators are looking into whether the attack is tied to protests of a drag show that took place Saturday, though Moore County Sheriff Ronnie Fields said there is no evidence at this point to link the two events.

Gov. Roy Cooper (D) said Monday the attack “raises a new level of threat” following a briefing with investigators and Duke Energy. He said state leaders would look into ways to harden the electrical grid.

“Violence and sabotage will not be tolerated,” Gov. Cooper said, adding that the motive is still unknown.

The attack came just a few days after the U.S. Dept. of Homeland Security issued a bulletin to law enforcement noting that “The United States remains in a heightened threat environment.”

“Threat actors have recently mobilized to violence, citing factors such as reactions to current events and adherence to violent extremist ideologies,” the bulletin reads. “Targets of potential violence include public gatherings, faith-based institutions, the LGBTQI+ community, schools, racial and religious minorities, government facilities and personnel, U.S. critical infrastructure, the media and perceived ideological opponents.”

When asked about the likelihood of a similar attack happening elsewhere, Schanzer said, “In my experience in looking at this for the last 20 years, that’s generally kind of rare. But, I also think when we’re going down to the substation level, those are vulnerable targets.”

Furthermore, Duke Energy said that the incident knocked out power for 45,000 customers, which is nearly all of the utility’s customers in Moore County. As of Monday afternoon, that number had dropped to 38,000 customers still affected.

Because of the extent of the damage, Duke Energy said people should prepare for the potential for power to be out until Thursday.

Schanzer said he hadn’t heard of an attack on physical infrastructure like what occurred Saturday night having this large of an impact on a community before.

“The principal concern would be really large-scale kinds of attacks that could bring down even larger swaths than what happened in Moore County,” Schanzer said. “I think when you’re looking at an electrical substation, that’s going to be pretty hard to protect and harden the infrastructure down to those kinds of micro-levels.”

Schanzer also noted the threat law enforcement officers could face in trying to apprehend whoever is involved.

“There’s a question about how dangerous these individuals are if it’s determined whom they are and what kind of firepower they have. And, if they’re going to be arrested, what law enforcement might be facing,” he said.