"World News Tonight With David Muir" Podcast - May 13, 2015

Amtrak 188 - Tragedy on the Tracks: In Philadelphia, an Amtrak train derailed and it's been revealed that the train was oging more than 100 miles per hour at the time of the crash. 

Officers attacked: A moment of terror on the streets of New York when a suspect was swinging a hammer and attacked an NYPD officer in broad daylight.  

Missing Helicopter: In Nepal, after the devastating earthquake, an American miltiary helicopter that rushed to the scene to help, vanished without a trace. 

Home Invasion: New developments in a terrifying home invasion in California.