Brazilian presidential candidate Eduardo Campos has reportedly been killed when his private jet crashed in the city of Santos in Sao Paulo, according to local TV network GloboNews.
Campos, 49, is a former governor Pernambuco state.
He positioned himself as a business-friendly leftist and was a former ally of President Dilma Rousseff, who is seeking a second term.
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His representatives said Cassidy, who was hospitalised last week, died "surrounded by those he loved."
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