It is widely suspected that child killer Robert Black committed a number of murders that have been unsolved for decades.
Despite never admitting to his crimes in court, Black has been linked to the killings of young girls and teenagers who disappeared from various locations across the UK, Ireland, Germany and France.
True Detective magazine has named 14 murder victims who vanished throughout the late 1960s, 1970s and 1980s, but whose cases remain unsolved.
Among them is April Fabb, who was last seen cycling to a relative's home in Norfolk on April 8, 1969 before she vanished.
Black was interviewed over the disappearance, but no link was found.
Also named was Mary Boyle, who disappeared from Ballyshannon in Co Donegal in March 1977. Black was known to have made deliveries in his van in the area and visited local pubs.
Pamela Hastie was raped and strangled as she walked home in Renfrewshire in November 1981. Her body was found in woodland. It later emerged that a van driver told police he crashed into a man running out of the woods on the night of the killing, identifying Black. But officers disregarded the evidence, saying the killer was not in the area at the time.
Another girl, Tracey Waters, was never seen alive again after heading to a youth club in Renfrewshire in February 1983. Her battered body was found in a garden half-a-mile from her home.
Others include Lisa Hession, from Manchester, Silke Garben, from Germany, and Sabine Dumont, Virginie Delmas, Hemma Greedharry and Perrine Vigneron, all of whom vanished in Paris in the 1980s.