Farm labourer John William Cooper was in the habit of taking long evening walks with a shotgun hidden underneath his jacket, a jury heard today.

  Cooper's son, Andrew, told Swansea crown court via video link his father had been "loud, strong, fit and aggressive."

  Cooper senior, aged 66, is accused of murdering brother and sister Richard and Helen Thomas at their home, Scoveston Park, in 1985 and also murdering holidaymakers Peter and Gwenda Dixon in 1989.

  All four had been shot dead.

  Cooper, of Spring Gardens, Letterston, is also charged with raping a 16 year old girl in March, 1996, in a field off the Mount estate, Milford Haven, indecently assaulting her friend and trying to rob them and their three friends.

  The youngsters were attacked by a masked man holding a shotgun.

  Cooper denies all the charges.

  Andrew Cooper was shown photographs of a gun found in a hedgerow near Cooper's then home in St Mary's Park, Jordanston. The prosecution say that years later a forensic scientist found a speck of Peter Dixon's blood on the barrel.

  Mr Cooper said it looked "very similar" to the one his father used to carry and that a length of cord attached to the gun was once used by his mother as a dog lead.

  Cross examined by Mark Evans, a barrister representing Cooper senior, he agreed that when police had shown him pictures of the same gun in 1998 and in 2008 he had not recognised it.

  He denied telling the jury what he thought the prosecution wanted him to say.

  Psychologist Jenny Bunton said she interviewed Cooper when he was part way through a 16 year jail sentence imposed for 30 burglaries and a robbery.

  She said he continued to deny most of the offences, claiming that a Gareth Martin had been responsible. He admitted acting as a lookout during some burglaries but denied entering the houses.

  Of the robbery at Sardis he said Gareth Martin had been in the house while Cooper stayed in a field and kept watch. He heard a house alarm go off and ran away.

  He said he broke into garden sheds and garages, but not houses.

  The trial continues.