A coroner in Wales is reviewing the 50-year-old deaths of siblings Griff and Martha Thomas after police re-examined forensic evidence in the case, which has long been linked to serial killer John Cooper, dubbed the "Bullseye" killer. The siblings, aged 73 and 70, were found dead at their isolated farmhouse in Milford Haven, Pembrokeshire, in December 1976, in a scene described by a family member as a "bloodbath". Their family and friends have never accepted the original police finding that Griff killed his sister before dying in a fire he started himself, insisting instead that both were murdered.

Martha was found with severe head injuries, slumped over a magazine rack, while her brother Griff's burnt body lay nearby; the bodies were discovered by a postman who noticed unopened post and the smell of burning. A 1977 inquest concluded Martha had been unlawfully killed by Griff, despite his physical disabilities, before he lay down and died in the blaze he allegedly started. Suspicion has since fallen on Cooper, now 81, who was convicted in 2009 of a string of murders, rapes and armed robberies across south Wales in the 1980s and 1990s after cold-case detectives matched a police e-fit to his 1989 appearance on the TV show Bullseye.