Survivors and relatives of victims carry Kenya's national flags on the anniversary of last year's deadly attack on the Westgate shopping mall in Kenya's capital of Nairobi. Thomas Mukoya/Reuters /Landov hide caption

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The first formal charges have been filed in the attack and standoff at a Nairobi mall that left at least 67 people dead. Four men are charged with aiding terrorism. Ben Curtis/AP hide caption

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The upper parking lot entrance to the Westgate Mall is seen above vehicles that plunged during the collapse of the upper level. Kenyan officials are urging patience with the pace of the flow of information about the attack. Ben Curtis/AP hide caption

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Civilians try to move to safety in a Nairobi shopping mall, where a standoff that began Saturday has lasted into Sunday. Images and witness accounts depict harrowing scenes inside the mall. AFP/AFP/Getty Images hide caption

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Kenyan soldiers secure a section of Nairobi's upscale Westgate Mall, in this image taken from AFP TV. At least 68 deaths have been reported as a result of Saturday's midday attack by gunmen at the mall. Nichole Sobecki/AFP/Getty Images hide caption

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