Today in Pictures: Texas Memorial Services, Presidents Together, Pope Appeal

Honor guards stand in front of caskets prior to a memorial service for first responders who died in last week's fertilizer plant explosion in West, Texas, April 25, 2013, at Baylor University in Waco, Texas. Firefighters and other first responders were among those killed when a fire at the plant erupted in an explosion last week. Hundreds of people were injured. (Eric Gay/AP Photo)

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