A private jet carrying Brazilian presidential candidate Eduardo Campos has crashed, sources in his political party told Reuters.
The plane lost contact with air traffic control as it was preparing to land in Santos, Sao Paulo, according to an Air Force statement.
A police official in Santos said there were "certainly" fatalities in the crash, but could not provide any additional information.
The party source, who spoke on condition of anonymity, said Campos' running mate, Marina Silva, was not on board.
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