When gunshots pierced the air outside the Washington Nationals ballpark, fans were sent into a terrifying panic as they tried to escape what many feared to be a mass shooting. Would you know what to do in a nightmare scenario like this? Inside Edition spoke with security expert Bill Stanton, who gave advice on how to stay prepared when entering large stadiums and arenas. “Wherever you go, know where your exits are. Do a quick walk around to scope things out,” he said.