Massive blackout hits Brazil's major cities

RIO DE JANERIO, Nov. 10 (Xinhua) -- A massive electricity outage hit Brazil's two largest cities of Sao Paulo and Rio de Janeiro on Tuesday, leaving millions of people in the dark.

Vehicles drive past dark buildings as a major blackout affected a large part of Brazil, in Sao Paulo November 10, 2009. REUTERS/Mario Miranda

The government has confirmed that the power failure was due to problems at the Itaipu dam, the world's second biggest hydroelectric producer which supplies 20 percent of Brazil's electricity.

The Brazilian director of the dam on the border of Brazil and Paraguay told a radio station that the power output of the entiredam was down.

The exact cause of the power failure is still unknown.

Other major cities, including the capital Brasilia, were also affected by the power cut, according to the website of Globo TV.