Major power failures hit Brazil

A power blackout in Brazil left tens of millions of people sitting by candlelight, after plunging its two largest cities into darkness. Underground railways, traffic lights, street lamps, lifts and electric gates in Sao Paulo and Rio de Janeiro were all affected.

It was several hours before the problem could be fixed.

The authorities believe it could have been caused by a fault at the giant Itaipu hydroelectric dam.

The underground railway systems in Rio de Janeiro and Sao Paulo shut down, after the power cuts hit soon after 2200 (0000 GMT), leaving many passengers stranded. 

Thousands of rail passengers had to walk down underground tracks to reach stations.

No traffic lights or street lights were working, causing traffic to stop or slow to a crawl. Extra police were put on the streets to prevent a surge in crime.

Electricity supplies in Paraguay, which shares power from Itaipu, were also disrupted for a short while.

The power system lost 17,000 megawatts after the massive plant went offline, possibly because of a storm.

The director of the dam said it had lost its entire hydroelectric output.

The BBC's correspondent in Sao Paulo, Gary Duffy, says the power cut happened at a time when millions would have been watching the country's popular soap opera on TV.

He adds that neighbourhood blackouts are common in the city of 19 million, but the scale of this power cut was remarkable.

The power failure also affected the south-eastern states of Minas Gerais and Espirito Santo, the south-western state of Mato Grosso do Sul, parts of the central state of Goias, and the federal district of Brasilia, although the capital itself was unaffected.

In all, nine of Brazil's 27 states were affected.
The Itaipu dam provides Brazil with 20% of its electricity.

In Paraguay, which relies on the Itaipu dam for 90% of its electricity, the entire country was blacked out for 15 minutes.