Fighters from the Islamic State of Iraq and Syria march in Raqaa, Syria, in a picture posted on Jan. 14. The group is believed to hold as much as $2 billion. AP hide caption

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Smoke rises above Jinnah International Airport Monday morning, following a five-hour firefight between security forces and militants. The facility was open for business Monday afternoon. Shakil Adil/AP hide caption

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A bomb blast and explosions that followed killed more than 70 people and injured more than 120 on Monday near Nigeria's capital, Abuja. Early speculation is that the attack was the work of the Boko Haram extremist group. /EPA/Landov hide caption

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Pakistani security personnel examine the site of a suicide bombing in the Ibrahimzai area of Hangu, Pakistan, on Monday. The bombing killed 15-year-old Aitizaz Hasan, who prevented the bomber from attacking a school. Basit Shah/AFP/Getty Images hide caption

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A woman wiped away tears Monday in Volgograd, Russia, after the second suicide bombing in that city in the past two days. Denis Tyrin/AP hide caption

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Libyan protesters burn a replica of the U.S. flag on Monday during a demonstration against the capture of Abu Anas al-Libi. U.S. forces seized him Saturday in the Libyan capital Tripoli. He is accused of involvement in two U.S. embassy bombings in Africa in 1998 and is being held on a U.S. Navy ship in the Mediterranean Sea. Esam OmranAl-Fetori/Reuters/Landov hide caption

itoggle caption Esam OmranAl-Fetori/Reuters/Landov

Pakistani rescue workers, police officers and civilians look for people who were wounded and killed at the site of a car bomb explosion in Peshawar, Pakistan, Sunday. Mohammad Sajjad/AP hide caption

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Kenyan police officers take cover outside the Westgate mall in Nairobi on Monday. Simon Maina /AFP/Getty Images hide caption

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Kenyan soldiers outside the Westgate shopping mall in Nairobi on Monday. Inside, attackers had killed dozens of shoppers, wounded more and it was feared they also had hostages. Daniel Irungu /EPA/Landov hide caption

itoggle caption Daniel Irungu /EPA/Landov

A Yemeni soldier searches a car near the airport in the capital, Sanaa. The United States has ordered Americans to leave Yemen immediately amid a warning of a possible attack. Mohammed Huwais/AFP/Getty Images hide caption

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A Yemeni soldier stands guard Tuesday near Sanaa International Airport. Mohammed Huwais /AFP/Getty Images hide caption

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