Moore County, North Carolina, has declared a state of emergency as power outages continue after a "deliberate" attack over the weekend in which gunfire damaged two substations."That leaves us with no option but to replace large pieces of equipment — which is not an easy or quick task," said Hollifield said.The outage has also rendered wastewater pumps in the area out of order, and schools in the county have been closed.In January, a bulletin from the Department of Homeland Security, obtained by CBS News, warned that domestic violent extremists "have developed credible, specific plans to attack electricity infrastructure since at least 2020, identifying the electric grid as a particularly attractive target.""There's a very few number of substations you need to take out in the entire United States to knock out the entire grid," Jon Wellinghoff, former chairman of the Federal Energy Regulatory Commission, told "60 Minutes" correspondent BIll Whitaker."