Big questions remain in wake of North Carolina power grid attack

The FBI is joining the investigation into power outages in Moore County, North Carolina, believed to have been caused by “intentional” and “targeted” attacks on substations that left around 40,000 customers in the dark. The mass outage turned into a criminal investigation when responding utility crews found signs of potential vandalism of equipment at different sites, according to the Moore County Sheriff’s Office. CNN’s Whitney Wild reports.