20 years on, man held for clifftop murders

IRA was originally blamed for execution-style killings

When the bodies of Peter and Gwenda Dixon were discovered riddled with gunshot wounds beside a Welsh coastal path 20 years ago, detectives pursued theories about the identity of their killers ranging from drug smugglers to an IRA cell in what became one of Britain's most perplexing unsolved murders.

Two years ago, police announced a cold case review of the execution-style killings of the nature-loving couple and refused to rule out a link with another double murder committed four years earlier 10 miles from where the Dixons were found. Helen and Richard Thomas, a brother and sister, were tied up and shot dead at their Pembrokeshire manor house in 1985.

Yesterday, the possibility was raised of a solution to the two long-running murder inquiries when detectives arrested a 64-year-old man in the street of a Pembrokeshire village on suspicion of carrying out the four gruesomely violent killings and a serious sexual assault on a teenage girl in 1996 in a field close to the Thomas family's home.

It is understood that the man, detained in Letterston, near Fishguard, at 8.15am, had been arrested more than 10 years ago in connection with the double murders but released without charge.

The latest arrest comes after Dyfed-Powys Police conducted a forensic re-examination of the evidence gathered in the murder investigations using the latest techniques to analyse DNA along with microscopic fibres and skin particles.

A police spokesman said: "A 64-year-old man has been arrested in connection with the double murders. He is in custody and being held for questioning."

Senior officers have long been struck by the considerable similarities between the killings. Richard and Helen Thomas's bodies were found in the burnt-out remains of Scoveston Manor, their substantial mansion in the village of Steynton near Milford Haven, three days before Christmas in 1985.

Ms Thomas, 54, is thought to have been at home alone when the killer broke into the house, tied her up and fired a shot gun against her head at point blank range. When her brother, 58, a millionaire farmer, returned home from a walk a short time later, he was also shot.

The murderer set fire to the house in an attempt to cover up the crime and detectives initially believed a domestic dispute between the siblings had caused a murder-suicide.

Forensic evidence quickly showed that the pair had been murdered but despite the offer of a reward and the search for a suspect described as a 20-stone bearded man driving a Rover car, the trail went cold.

Four years later on 19 June 1989, the Dixons, from Witney in Oxfordshire, who had been married for more than 30 years, began their annual two-week camping trip to the Pembrokeshire coast in south-west Wales, where they liked to go rambling and bird spotting.

On 29 June they set out at about 9.30am from their tent on a campsite near Little Haven to a woodland less than a mile away along a cliff-top path to spot a pair of nesting peregrine falcons. Their stroll took them into the way of a particularly cruel killer.

Mr Dixon, 51, a marketing manager, had his hands tied behind his back. Police believe he was probably forced to watch as the murderer fired at his 52-year-old wife, a secretary and badminton player, at point blank range with a shot gun. Her clothing was disturbed, suggesting she may also have been sexually assaulted.

Mr Dixon, an amateur radio enthusiast, was also murdered and his wallet, containing seven bank and credit cards, a phone card and his driving licence, was stolen.

The bodies of the couple were hidden in the undergrowth. Although witnesses described hearing gun shots at about 11am, no one noticed that the Dixons' red Ford Sierra outside their tent had not moved until their son, Timothy, raised the alarm when they failed to return from holiday. Police tracker dogs found their bodies on 5 July. Early on, the investigation focused on the fact that Mr Dixon's NatWest cash card was used on three occasions within three days to withdraw £310 at banks in the nearby towns of Pembroke, Carmarthen and Haverfordwest.

The description of the man using the card, a scruffily-dressed cyclist, tallied closely with what became known as the "Wild Man" suspect, who had been seen several times on the footpath where the Dixons died.

He was aged 30 to 40, about 6ft tall, tanned and unshaven with long greasy hair and pushing an old-fashioned bike. He was carrying a haversack which one witness described as being "big enough to hold a gun".

But despite huge publicity and a police team of 150 officers taking 6,000 statements and interviewing 17,000 people across Britain, the killer was not found.

A series of theories were investigated and discounted, including the suggestion that the Dixons had stumbled on to an IRA group who were hiding or retrieving arms.

The suggestion was given some credence when police discovered an arms cache just a few miles from the murder scene in the autumn of 1989, but no link to the crime was proven.

Detectives also investigated whether drug smuggling gangs who use the Welsh coastline could have been responsible.

The case was never closed and in November 2007, the Dyfed-Powys force set up Operation Ottaw, the cold case review which is believed to have made the breakthrough using DNA technology.

Kevin Dixon, Peter's brother, said at the start of the cold case review: "You don't come to terms with grief, you carry it discreetly but it leaves a mark. The police have been tenacious – they don't give up. We would like to see somebody brought to account. It doesn't make our loss any better or easier to carry but it will give us a sense of closure."