DNA Identifies Six Long Island Cold Case Victims

New DNA testing has helped Suffolk County investigators identify six people whose remains were found in Long Island cases dating back as far as 1976. Three are believed to have been homicide victims. The technology was also used in the investigation that led to the 2023 arrest of Gilgo Beach killer Rex Heuermann, Suffolk County District Attorney Ray Tierney said.

One victim, previously known as “Montauk Mary,” was identified as Sofia Margherita Marrone, 73. Her body was found in Montauk in 1978 with four gunshot wounds to the chest. Investigators suspect serial killer Richard Biegenwald may have killed her: the ammunition was the same type of .22-caliber short rounds used in his killings. Authorities said they could not confirm he was responsible. Biegenwald, known as the “Thrill Killer,” died in prison in 2008.

The other identifications include Ramon Perez Y Rivera, 41, found in Deer Park in 1976 with a gunshot wound; Antionette Rugg, 27, whose remains were discovered in Islip in 1978 with a belt around her neck; and Kyong-Ok Kim, 32, whose remains were discovered in Riverhead Town in 1990. Kim’s cause of death remains under investigation.

Also identified were Omelios Steward, 27, found in 1990 and believed to have drowned, and Andreas Kupke, 27, found in 1999. Kupke’s cause of death is unclear. Tierney said the identifications gave relatives answers and advanced efforts to pursue justice.

Suffolk County has about 244 unsolved death cases from 1970 to 2025, with roughly 210 victims still unidentified. Tierney said investigators continue working to identify them and will use the DNA technology where possible.