Brittany Clark, 31, dies after a roughly 13-foot alligator attacks her while she wades in shallow water at the Econlockhatchee River; emergency responders take her to a hospital but she dies en route.Her boyfriend, Chance Allison, and friend Jayden Hernandez are present; Allison tries to free Clark, sustains serious injuries, and a 911 call captures his pleas for help as she loses blood and one arm is severed.The Florida Fish and Wildlife Conservation Commission captures and euthanizes two large alligators, preserves the suspected animal for analysis, and says there is no evidence the attack was provoked while low water and mating season may have increased risk.