Some central parts of Los Angeles lost power for more than an hour last night after utility workers accidentally cut several cables.
Some two million people were affected by the resultant power surge and power cut.
The power cut began at about 12.30pm when workers installing an automated alert system cut several wires simultaneously, instead of one at a time.
At the height of the blackout, many office workers seized the chance for an extended lunch on a mild afternoon.There were few reports of injuries.
Police discounted terrorism almost immediately, although Mayor Antonio said the timing "created a heightened sense of concern."
The power cut came a day after the airing of videotape in which a purported al-Qaeda member threatened Los Angeles.
