A massive power failure blacked out Brazil's two largest cities and other parts of Latin America's biggest nation overnight, leaving millions of people in the dark after a huge hydroelectric dam suddenly went offline.
Paraguay was also affected when the Itaipu dam straddling the two nations' border stopped producing 17,000 megawatts of power, resulting in outages in Rio de Janeiro, Sao Paulo and at least several other big Brazilian cities.
The cause of the failure had not been determined, but Edison Lobao, the Brazilian Mines and Energy Minister, said strong storms had uprooted trees near the Itaipu dam just before it went offline and could be to blame.
Rio de Janeiro, which is due to host the World Cup soccer championship in 2014 and the Olympic Games in 2016, was the hardest hit city. Rio’s famous Copacabana beach, usually illuminated by the bright lights from the skyscrapers lining the boulevard, was plunged into darkness.