A former North Carolina Marine with ties to white supremacy pleaded guilty Tuesday in connection with a plot to damage a power grid somewhere in the northwest U.S., according to federal prosecutors.

Jordan Duncan, 29, pleaded guilty to aiding and abetting the manufacturing of a firearm, according to the U.S. Attorney's Office in Raleigh. Duncan, who faces up to 10 years in prison, was the last of five to be charged in the attack. The former Marine was assigned previously to Camp Lejeune in Jacksonville, North Carolina.

"According to court documents, Duncan, with co-defendants, Paul James Kryscuk, 38, Liam Collins, 25, Justin Wade Hermanson, 25, and Joseph Maurino, 25, researched, discussed, and reviewed at length a previous attack on the power grid by an unknown group. The group depicted in the attack used assault-style rifles in an attempt to explode a power substation," a release from the U.S. Attorney's Office states.

Duncan, Kryscuk and Collins were previously indicted on charges of planning to illegally manufacture and sell guns, officials said.

Between 2017 and 2020, Kryscuk manufactured firearms while Collins — who was stationed at Camp Lejeune in North Carolina — stole military gear, including magazines for assault-style rifles and had them delivered to the other defendants, prosecutors said. During that time, Duncan gathered information on firearms, explosives and nerve toxins and shared it with Kryscuk and Collins, according to prosecutors.

In October 2020, a handwritten list of 12 intersections and places in Idaho and surrounding states was discovered in Kryscuk’s possession, including locations of a transformer, substation, or other component of the power grid for the northwest United States, the U.S. Attorney's Office says.

A previous indictment says the men discussed using a homemade combination of metal powder and metal oxide, which burns at over 4,000 degrees Fahrenheit (2,200 degrees Celsius), to burn through and destroy power transformers.

In mid-2020, Collins asked others to each purchase 50 pounds (23 kilograms) of an explosive, authorities said. 

Previously filed charges alleged that Collins and Kryscuk were members of the “Iron March” and posted in the group forum, a gathering point for young neo-Nazis to organize and recruit for extremist organizations. The forum was closed in late 2017.

"Collins and Kryscuk met through the forum and expanded their group using an encrypted messaging application as an alternate means of communication outside of the forum. Collins and Kryscuk recruited additional members, including Duncan, Hermanson, and Maurino, and conducted training, including a live-fire training in the desert near Boise, Idaho," according to the U.S. Attorney's Office.

In video recorded by the members during the training, participants are seen firing short barrel rifles and other assault-type rifles, and the end of the propaganda video shows the four participants outfitted in AtomWaffen masks giving the “Heil Hitler” sign, beneath the image of a black sun, a Nazi symbol, a release from the U.S. Attorney's Office states. The last frame reads, “Come home white man,” according to court records. 

Duncan was stationed at Camp Lejeune when he joined the group. He moved to Idaho in 2018 after separating from the Marines and discussing the shooting of protesters with a group member who had been observing Black Lives Matter rallies in Boise, Idaho, the indictment said. Less than a month later, FBI agents notified two BLM movement co-founders that their names were on a list kept by a different paramilitary group member, prosecutors said.

On February 15, 2022, Kryscuk entered a plea of guilty to conspiracy to destroy an energy facility, according to the U.S. Attorney's Office. On October 24, 2023, Collins pleaded guilty to aiding and abetting the interstate transportation of unregistered firearms. On March 8, 2023 and April 11, 2023, Hermanson and Maurino pleaded guilty to conspiracy to manufacture firearms and ship interstate. 

Duncan, a military contractor, served in the Marines from 2013 to 2018. Collins served in the Marines from 2017 to 2020. Hermanson was assigned to the same unit as Collins.

Duncan, Collins, Kryscuk, Hermanson and Maurino are awaiting sentencing.