Episode 127

Matt Rivers has the latest on the gunman with a semi‑automatic rifle opening fire in broad daylight outside Boston in Cambridge, appearing to shoot at random, sending people running for their lives; Victor Oquendo has details on new concerns about whether the hantavirus could spread more easily than initially thought as one of 18 U.S. passengers evacuated from the luxury cruise ship tests positive for the virus, and another shows mild symptoms; ABC News' Diane Sawyer shares a first look at her new special that highlights the final decade of Richard Simmons' life after he disappeared from the public view; and more on tonight's broadcast of World News Tonight with David Muir.