An eighth victim has died in a massacre in a Georgia trailer park, reports ABC News. Police have arrested a 22-year-old relative of one of the victims who authorities say called in the deaths on Saturday and was found with drugs. But police believe the killer is still on the loose. "There is somebody out there we're looking for," said the Glynn County police chief. "We just don't know who that person is." The lone survivor of the shooting is in critical condition. (More trailer park stories.)