(CNN) Attacks on the United States' power grid have been the subject of extremist chatter for some time, notably ticking up in 2020, the same year a 14-page how-to on low tech attacks, including assaulting power grids with guns, circulated amongst extremist communication channels.
A Department of Homeland Security bulletin reported by CNN just days before a weekend attack on a North Carolina substation indicated there was a heightened threat posed by domestic violent extremists in the US against targets including critical infrastructure.
The electric grid has been described as an "attractive target" for domestic violent extremists in US, CNN reported earlier this year, citing an intelligence report.
In 2020, intelligence analysts saw major uptick in online chatter focused on attacking the power grid.
Notably in 2020, a 14-page document released in a Telegram channel favored by accelerationists groups seeking to speed the overthrow of the US government featured a white supremacist instruction guide to low-tech attacks meant to bring chaos, including how to attack a power grid with guns.
The document has been cited by DHS officials and was obtained by CNN.
"The powergrid would be crippled for a very large area. Armor piercing rounds shot into the transformers would destroy them," the colorful how-to describes.
The writer goes on to frame how massive blackouts would aid in the toppling of society which is a key accelerationist goal.
"But with the power off, when the lights don't come back on... all hell will break lose, making conditions desirable for our race to once again take back what is ours," the document reads.
Several unique attempts to attack various grids have been cited by intelligence officials that analyze these specific threats.
Investigators discovered a four-rotor drone on July 16, 2020 in Pennsylvania recovered from the roof of a power station, according to a DHS bulletin in October 2021.
The drone had nylon cords that dangled below holding a two-foot section of copper wire, and the investigative theory is that the drone was to hover over the live high-voltage wires, then make contact with the lines with copper wire it dangled and short-out the station, according to the intelligence briefing.
CNN reported earlier this year that In May 2020, three people claiming to be Boogaloo adherents allegedly conspired to attack an electrical substation in Las Vegas as part of an attempt to incite riots and violence amid demonstrations in the city.
The suspects were charged with conspiracy to damage and destroy by fire and explosives and with possession of unregistered firearms.
A DHS bulletin reported by CNN just days ago indicated there was a heightened threat posed by domestic violent extremists in the United States, against in part, critical infrastructure targets.
On November 30th, DHS renewed a national bulletin warning that lone offenders and small groups motivated by a range of ideological beliefs and personal grievances pose a lethal threat to the US.
The advisory said in part "DHS maintained that potential targets include but are not limited to public gatherings, faith-based institutions, the LGBTQIA+ community, schools, racial and religious minorities, government facilities and personnel, US critical infrastructure, the media and perceived ideological opponents."
The unsolved case of the attack on the Metcalf Pacific Gas and Electric substation in Coyote, California, on April 16, 2013 set the bar for these types of attacks and has been a case study for intelligence officials
According to several in person briefings on this attack, two underground vaults were entered where fiber-optic cables were cut breaking down phone and internet service for much of the area.
Shortly after, at 1 a.m., over a hundred rounds fired at the station by snipers hit key transformers and an oil drum that caused 52,000 gallons of oil meant to cool the high voltage transformers to leak
The plant overheated causing an alarm to go off. Authorities believe the timing suggests they may have been monitoring the police radio because they had been firing for almost twenty minutes before leaving.
The vulnerabilities of the power grid have been closely examined by the Department of Energy, DHS and Congress.
According to the National Research Council, tasked by Congress to examine these vulnerabilities, the US grid consists of 6,400 power plants, 55,000 substations, 450,000 miles of transmission lines, and 3,000 companies.