Police in Las Vegas say a lone gunman is responsible for killing more than 58 people. We're now told that at least 500 people were taken to local hospitals. This is the deadliest mass shooting in U.S. history. The shooter targeted some 22,000 country music fans who were attending an outdoor festival. Police believe the gunman killed himself before police entered his room on the 32nd floor of the Mandalay Bay Resort and Casino, across the street from the concert. He is identified as 64-year-old Stephen Paddock.