Alleged killer John William Cooper made a “well engineered” burgling device, a jury in Swansea heard.

The tool was found in a field by detectives investigating a violent robbery in 1996, along with a gun later found to have the blood of Peter Dixon, from Moorland Road, Witney, on one of the barrels.

Cooper, 66, of Letterston, West Wales, denies murdering Peter and Gwenda Dixon, aged 51 and 52, in 1989. Cooper has also denied two other murders, a rape, indecent assault and five attempted robberies.

The trial continues.