Security guards were deployed outside the graffiti-covered walls of the U.S. Embassy in Cairo, Egypt, which came under attack Tuesday. Mohamed Abd El Ghany/Reuters/Landov hide caption

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This 2010 image, provided by IntelCenter, shows Humam Khalil Abu-Mulal al-Balawi in a posthumous video message posted on extremist websites. The al-Qaida double agent killed seven CIA operatives, a Jordanian spy and himself when he set off a bomb strapped to his body at a base in Afghanistan in December 2009. AP/IntelCenter hide caption

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Outgoing Yemeni President Ali Abdullah Saleh speaks to the press at the presidential palace in Sanaa on Jan. 22. AFP/Getty Images hide caption

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Protesting Yemeni women burn their veils, during a demonstration demanding the resignation of Yemeni President Ali Abdullah Saleh in Sanaa, Yemen.

Hani Mohammed/AP hide caption

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In the capital, Sanaa, on Sunday, some Yemeni anti-government protesters celebrated Saleh's departure. AFP/Getty Images hide caption

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