An ER doctor was killed after being mown down by a Lexus and then stabbed to death by the driver in an apparent road rage incident. Dr Michael Mammone, 58, was cycling on the Pacific Coast Highway, California, when he was run over by a white Lexus which sped through a red light at an intersection on Wednesday at around 3pm. The driver of the vehicle, Vanroy Evan Smith, 39, then got out of his car and stabbed the cyclist multiple times in the back, with brave bystanders tackling him to the ground. Witnesses say he was holding a BB...