Investigators and first responders work near the wreckage of Amtrak Northeast Regional Train 188, which derailed May 13, 2015, in north Philadelphia. Eight people were killed and hundreds injured in the crash.
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Smoke inhalation victims walk past a firefighter towards a medical aid bus Monday after passengers on the Washington, D.C., subway were injured when smoke filled the L'Enfant Plaza station during the afternoon rush hour.
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