Rio de Janeiro, Brazil (CNN) -- Electricity returned early Wednesday to a large swath of central and southern Brazil that was plunged into darkness when power from a major hydroelectric dam was lost. Up to 18 of Brazil's 26 states were left without power when electricity from the Itaipu dam was interrupted around 10:15 p.m. (7:15 p.m. ET) Tuesday, leaving Sao Paulo, Rio de Janeiro and other cities in darkened chaos. Hundreds of people were trapped in elevators. Subways, trains and buses stopped running their routes. Video showed long snaking lines of cars at a near standstill on the roads, their headlights the only illumination.
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Electricity returns to central and southern Brazil after power from major hydroelectric dam was lost
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Neighboring Paraguay, Uruguay report related blackouts
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Hydroelectric dam provides over 20 percent of Brazil's energy
The Itaipu dam, one of the world's largest hydroelectric facilities, is shared by @placeholder and Paraguay, which also lost power.