Terrified neighbors implored dispatchers to send police as a voice in the background screamed for help in 911 recordings released after the shooting of an unarmed Florida teen. Trayvon Martin, 17, was returning from the store to the Sanford home of his father's fiancee when he has shot last month. Authorities released seven 911 calls Friday, all of which describe hearing a gunshot. The teen's parents broke down when they heard the recordings detailing the last moments of his life, said their...