Embattled Brazilian President Dilma Rousseff (shown here at the 21st International Construction Salon in Sao Paulo, Brazil, on Tuesday) was elected four months ago. Her administration has been hit hard by economic problems and a massive corruption scandal at the state oil company, Petrobras. Nelson Almeida/AFP/Getty Images hide caption

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Diego Lagomarsino, a computer expert who gave late prosecutor Alberto Nisman the gun that killed him, speaks to reporters during a press conference in Buenos Aires last month. Rodrigo Abd/AP hide caption

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Performers from the Beija-Flor samba school parade on a float during Carnival celebrations at the Sambadrome in Rio de Janeiro on March 3, 2014. That year, the Beija-Flor parade was centered on a theme of communication throughout history; this year's theme, underwritten by Equatorial Guinea, is more controversial. Felipe Dana/AP hide caption

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A demonstrator dressed as a bather protests against the rationing of water, outside the official residence of Sao Paulo's Governor Geraldo Alckmin in Sao Paulo, on Jan. 26. The banner behind him reads, "Planet Water, Dry Lives." Andre Penner/AP hide caption

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Argentine Foreign Minister Hector Timerman arrives to give a press conference at the presidential palace Casa Rosada, in Buenos Aires, on January 15, 2015. Alejandro Pagni /AFP/Getty Images hide caption

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Argentina's Foreign Minister Hector Timerman on Jan. 15 shows a letter he said was sent in 2013 to Interpol informing it of an agreement reached with Iran's government to investigate the 1994 bombing of the Argentine-Israeli Mutual Association that killed 85 people. Timerman says he met with Iran in an attempt to solve the case and denies accusations he was part of a cover-up. Rodrigo Abd/AP hide caption

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