By Daily Mail Reporter Last updated at 3:26 PM on 10th September 2011 A major power outage, which left more than six million people in California and Arizona in darkness, was caused by a single maintenance worker, it has been revealed. The power cut took two nuclear reactors offline, grounded flights, caused major traffic jams and trapped people in elevators and on fairground rides in both states. San Diego bore the brunt of the blackout and most of the nation's eighth-largest city was darkened. The city trolley system that shuttles thousands of commuters every day was shut down and rush hour traffic hit gridlock.
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Authorities say a worker triggered the blackout when he removed a piece of monitoring equipment at a power substation
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Power begins coming back for affected residents in Southern California, Arizona and Mexico early Friday morning
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Vandalism and robberies reported at San Diego-area homes and businesses
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Minor traffic accidents reported as outage caused mayhem on streets without stoplights
The error, on a high-voltage power line linking @placeholder and San Diego, causing a cascading series of electrical grid failures stretching into Southern California.