U.S.-backed Juan Guaidó takes oath of office as head of the assembly after lights are cut, in the latest twist to nation’s intensifying political crisis

Mr. Guaidó had been expected to easily win re-election on Sunday. But after keeping him and other opposition deputies out, pro-Maduro lawmakers quickly named Luis Parra, a lawmaker who broke from the opposition alliance, as head of a pro-government assembly. Latin American powers condemned the move, while U.S. officials said they are considering tougher sanctions on the Maduro regime.

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