A fresh forensic review has been carried out in the case of two siblings who died nearly 50 years ago, the Western Telegraph reports. Retired farmer Griff Thomas and his sister, Martha, were found dead in their burning farmhouse in Ffynnon Samson in Pembrokeshire in 1976. Griff and Martha Thomas were found dead at their farmhouse in Llangolman, Pembrokeshire, shortly before Christmas in 1976. A fresh forensic review has now been carried out into the case nearly 50 years on. The Llangolman farmhouse where siblings Griff and Martha Thomas were found dead shortly before Christmas in 1976.