Accused Gilgo Beach serial killer Rex Heuermann has been charged in the death of a seventh woman.Heuermann is charged with one count of second-degree murder in connection with the murder of Valerie Mack, according to a superseding indictment unsealed Tuesday.Mack, whose remains were first found on Long Island in 2000. Mack, 24, had been working as an escort in Philadelphia and was last seen by her family that year in New Jersey. Learn more about your ad choices. Visit podcastchoices.com/adchoices