Just three days before two electrical substations were shot up, causing tens of thousands of customers to lose power in North Carolina, the federal Department of Homeland Security issued a bulletin warning "lone offenders and small groups" could be plotting attacks and that the nation's critical infrastructure was among the possible targets.
The warning became a reality on Saturday when widespread power outages in North Carolina were reported after a perpetrator or perpetrators shot up the power stations in Moore County. The incident left up to 45,000 utility customers without electricity and prompted local officials to declare a state of emergency.
The Homeland Security "National Terrorism Advisory System Bulletin" issued on Nov. 30 said individuals and groups motivated by a range of ideological beliefs and personal grievances "continue to pose a persistent and lethal threat to the Homeland."
"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," the bulletin reads.
The bulletin followed one issued by the Department of Homeland Security in January, warning that domestic extremists have been developing "credible, specific plans" to attack electricity infrastructure since at least 2020, according to the Associated Press.
While law enforcement investigating the Moore County sabotage has yet to identify a suspect or a motive, the attack has been described by local authorities as an "eye-opener" and prompted calls to harden the state's infrastructure to deter future incidents.
"This kind of attack raises a new level of threat," North Carolina Gov. Roy Cooper said at a news conference Monday afternoon.
But similar attacks and foiled plots suggest electrical grids and other infrastructure across the United States have been targeted over the past decade.
In April 2013, a group of suspects wielding high-powered rifles staged an attack in California's Silicon Valley, shooting up the Pacific Gas & Electric Company's Metcalf substation, riddling transformers with bullets, officials said. PG&E said the attack caused $15 million in damage and prompted the utility company to spend $100 million to beef up security at its substations, including installing intruder detection systems.
No arrests were made in the California attack.
"Metcalf was an interesting attack because they also attacked the fiber communications vault just up the street to try to interfere with the alarm and communication with the substation," Kevin Perry, retired director of critical infrastructure protection at Southwest Power Pool in Arkansas, told ABC News.
Unlike in Moore County, the attack failed to cause a major power outage.
"There's a lot of redundancy that's built into the grid. And in the case of Metcalf, even though the substation was taken out of service, (PG&E) was able to bypass the substation and continue to energize the area," Perry said.
Perry said most electrical distribution substations across the country are vulnerable to attacks because they are usually in remote areas and have little security.
"Substations tend to be out in the middle of nowhere, and that means they’re, for the most part, unattended," Perry said. "If you take out enough equipment then you lose the redundancy and when you lose the redundancy you don’t have any way of feeding power to that particular area, and that’s when you end up with a regional blackout."
In February, three men each pleaded guilty in Ohio to a federal charge of conspiring to provide material support to terrorists as part of a scheme to attack power grids in the United States in furtherance of white supremacist ideology, according to the Department of Justice. The men - one from Ohio, one from Texas and the third from Wisconsin -- met online and plotted to use high-powered rifles to attack electrical substations in different regions of the United States, the DOJ said in a statement.
"The defendants believed their plan would cost the government millions of dollars and cause unrest for Americans in the region. They had conversations about how the possibility of the power being out for many months could cause war, even a race war, and induce the next Great Depression," the DOJ's statement reads.
The plot was thwarted when two of the men were pulled over by police in Ohio for a traffic violation and one swallowed a "suicide pill" but ultimately survived, according to federal prosecutors.
In 2019, a Utah man pleaded guilty to one federal count of destruction of an energy facility stemming from a 2016 rifle attack on a Buckskin Electrical substation in Kane County and was sentenced to 96 months in prison, according to federal officials. The attack caused nearly $400,000 in damage and triggered a power outage in Kane and Garfield counties, officials said.
As part of the plea agreement, the defendant admitted causing damage to three substations in Nevada, but was not charged in those incidents, according to federal prosecutors.