Farm labourer John William Cooper went into the witness box today to deny any involvement in murder or rape - or any of the 31 crimes he was jailed for in 1998.

Cooper, aged 66, told a jury at Swansea crown court of the anger he still felt about spending, but for a few weeks, the last 13 and a half years in jail.

"I have an anger inside me that is hard to describe. But I don't use the negative side of it. I use the positive side to move on," he said.

Cooper, of Spring Gardens, Letterston, has begun to give evidence in his defence.

He said he had no involvement in the fatal shootings of brother and sister Richard and Helen Thomas, aged 58 and 56, who were murdered at their home in Scoveston Park in 1985.

He said he had never been on the Pembrokeshire Coastal Path where, in June, 1989, holidaymakers Peter and Gwenda Dixon, aged 51 and 52, were blasted to death by a killer with a 12 bore shotgun.

And he would have had no reason to be anywhere near a field off the Mount Estate, Milford Haven, in March, 1996, when a 16 year girl was raped, her friend indecently assaulted and five teenagers were ordered by a hooded gunman to hand over cash.

The prosecution claim that evidence linking Cooper to the crimes was found along a trail police believe was used by the man who carried out a robbery at Sardis in 1996. Cooper was later convicted of that crime and jailed.

Cooper said a balaclava found at the time was his - scientists found his head hair inside. He said it had been stolen from a cabin cruiser he owned.

He denied having anything to do with a sawn off shotgun also found on the Sardis trail, which had a speck of Peter Dixon's blood on one of the barrels.

Cooper said at the time of the Sardis robbery he had been keeping a diary of his health as his doctor and a consultant tried to help him with his arthritis. One entry said he had taken his dogs for a walk. The truth, he said, was that he had stayed in his car and the dogs had walked itself.

"I was not capable of robbing anyone," he added.

Another entry recorded how he had stumbled into a tree, and another of how he was not well enough to take part in a darts tournament, all around the time of the robbery.

Previously, the jury has heard how Cooper lived rent free for nine years after a "physical" with the owner of the house.

Cooper told police he carried out improvements at 34 St Mary's Park, Jordanston, to the value of the rent.

Swansea crown court has been hearing details of interviews with Cooper after his arrest in 2008 for the alleged murders of brother and sister Richard and Helen Thomas, aged 58 and 56, and of holidaymakers Peter and Gwenda Dixon, 51 and 52.

All four had been shot dead--the Thomases in 1985 at their home in Scoveston Park, near Milford Haven, and the Dixons four years later.

The Dixons, from Oxfordshire, were robbed after being shot as they walked the Pembrokeshire Coastal path on June 29, 1989. Mr Dixon's cash card was used to withdraw money from cashpoints in Pembroke Dock, Pembroke, Carmarthen and Haverfordwest during the following days. His gold wedding ring was also stolen.

Cooper said in 1989 he was working for Mike Richards, of Jordanston Farm, who would deduct from his wages rent for 34 St Mary's Park.

In April, 1989, there had been an incident in a farmyard involving Cooper and Mr Richards, described by Cooper as a "bust up" that became physical.

As a result, he lost his job and on May 3 received a letter telling him to quit 34 St Mary's Park.

Cooper took advice and replied to Mr Richards that he was protected under the Rent Act.

"I stayed on and did the same amount of rent by way of improvements to the house."

In another interview, he said, "It saddened me. It was stressful. I did not pay him any rent after that.

"If you fall out with your employer he can't put you out. After the letter I sent the notice was never followed up," he added.

Questioned by Detective Sergeant Gareth Rees, Cooper denied that he was the "scruffy" man seen pushing an old fashion bicycle close to one of the cash points at the time Mr Dixon's card was used.

An artist had created an image of the man from descriptions given by other users of the cash point.

Cooper said, "It does not resemble me. I shave every day. It makes me feel dirty if I don't."

He agreed that on July 5, 1989 a man signing his name as Cooper and giving his address had sold a gold wedding ring to a jeweller in Pembroke.

Cooper said he dealt in second hand jewellery and had bought and sold many wedding rings over the years. And between 1992 and 1996 he had dealt in stolen property.

He denied being the man who had removed Mr Dixon's wedding ring, before or after he was killed, and selling it in Pembroke.

Det Sgt Rees questioned Cooper about shotgun cartridges found buried under a duck run at 34 St Mary's Park, in particular a rare cartridge dating back to before World War Two.

It was known, said the officer, that Richard Thomas had kept cartridges from the same era.

Cooper said he didn't even know the cartridge was there.

"I didn't kill the Thomases," he said.

The trial continues.