A Navy pilot who flew with the Blue Angels — some of the group's planes are seen here last September — was killed in a crash southwest of Nashville on Thursday afternoon. Portland Press Herald/Press Herald via Getty Images hide caption

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Liverpool supporters were crushed against a barrier in 1989, in what became Britian's worst sports disaster. Some 96 fans died in the incident at the Hillsborough Stadium in Sheffield, England. David Cannon/Getty Images hide caption

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Rahul Gandhi (center left), vice president of the All India Congress Committee, and Adhir Ranjan Chowdhury (center, second from left), state president for West Bengal Pradesh Congress Committee, visit the site of a collapsed highway overpass in Kolkata on Saturday. Rescue officials said Friday there are no more survivors trapped under the rubble. AFP/Getty Images hide caption

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After an overpass partially collapsed in Kolkata, India, residents and rescue workers rushed to clear rubble and reach dozens of people who had been under the structure when its supports gave way. Bikas Das/AP hide caption

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The Metrojet Airbus A-321 with registration number EI-ETJ that crashed in Egypt's Sinai Peninsula is seen here last month, at an airport in Turkey. The Russian airliner crashed while carrying 224 passengers and crew, the Egyptian civil aviation authority says. Reuters /Landov hide caption

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Emergency personnel escort people away from the site of a collision in Puisseguin in southwestern France. At least 40 people, most of them elderly, were killed when a bus collided with a truck and caught fire in southwest France. Jean-Pierre Muller/AFP/Getty Images hide caption

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A relative of passengers on board the Eastern Star cruise ship is comforted by a man along the Yangtze River's banks in Jianli, China. Relatives of people missing after the cruise ship capsized have gathered at the disaster site. AFP/Getty Images hide caption

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Relatives await word of survivors from a cruise ship that capsized in the Yangtze River. The Eastern Star was carrying more than 450 people; only 14 have been rescued. China Stringer Network/Reuters/Landov hide caption

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