Miami (FL) - People in southern Florida were hit with a massive power outage after two nuclear reactors spontaneously shut down. The outage centered on the Miami-Dade area, but also extended to some parts of Broward County. Nuclear Regulatory Commission reps say the reactors were probably responding to a weird reading in the power grid and add that everything should be back to normal shortly.

Just before 1 PM Eastern Standard Standard time, two reactors at the Turkey Point plant automatically shut down. This caused rolling blackouts throughout much of southern Florida. NRC spokesperson Ken Clark told CNN that the reactors were "scrammed" or electronically shut down because of a disturbance in the power grid. He stressed that NRC officials do not know what caused the initial power problem.

Clark said the plants probably went into hot standby mode which means they could be restarted in a few hours.

Florida's Power & Light says 700,000 customers were affected. This is much lower than Florida's Emergency Operations Center initial estimation that 3 to 4 million homes were affected.