This aerial photo, workers comb through the debris after a train derailed causing explosions of railway cars carrying crude oil Tuesday, July 9, 2013 in Lac-Megantic, Quebec, Canada on

 

              This aerial photo, workers comb through the debris after a train derailed causing explosions of railway cars carrying crude oil Tuesday, July 9, 2013 in Lac-Megantic, Quebec, Canada on
This aerial photo, workers comb through the debris after a train derailed causing explosions of railway cars carrying crude oil Tuesday, July 9, 2013 in Lac-Megantic, Quebec, Canada on Tuesday July 9, 2013. At least thirteen people were confirmed dead and nearly 40 others were still missing in a catastrophe that raised questions about the safety of transporting oil by rail instead of pipeline. (AP Photo/ The Canadian Press, Paul Chiasson)