A father found dead in his car along with his two children at a remote beauty spot had been in touch with Fathers-4-Justice in the last week, the organisation has confirmed.

Brian Philcox, 58, a martial arts expert, was found dead in the Land Rover alongside his daughter Amy, 7, and son Owen, 3, in a country lane near Llanrwst in the Snowdonia National Park, north Wales.

Detective Chief Inspector Wayne Jones, of North Wales Police, said that all three had died from carbon monoxide poisoning after inhaling car exhaust fumes.

Mr Jones also confirmed that a bomb disposal unit was called to check the vehicle after Cheshire police officers found a "device" at Mr Philcox’s home address in the Windmill Hill area of Runcorn. The vehicle was given the all clear.

The three were reported missing by Mr Philcox's estranged wife, Evelyn, 37, at 11pm on Saturday when they failed to return to the family home in Runcorn after a day out.

It is understood that Mr and Mrs Philcox separated 18 months ago, and that he had arranged to have access to the children on Saturday to take them out for the Father's Day weekend.

"I can confirm that we believe that Mr Philcox had been in touch with Fathers-4-Justice last year, and also again recently," said Matt O'Connor, the founder of the group, which offers support to estranged fathers and campaigns for greater legal rights for them. "We are fairly certain that he had been in touch in the last week. We have an official helpline.

"He had been advised to join the group, via our internet site, but so far as we are able to tell he had not joined, unless he did so in the last week. There is a backlog of about 1,000 membership applications so it is not possible to say for certain yet."

Mr O'Connor described the deaths as a terrible tragedy, and offered the group's sympathy to Mrs Philcox and her family. He said that the case showed the despair felt by some fathers when their relationships broke down.

"We do get a lot of desperate calls around Father's Day and Christmas, the two most difficult times of the year."

Police were alerted to the bodies by a member of the public at about 3pm yesterday.

The children's deaths are being treated as suspicious and inquiries are continuing, but police say they are not looking for anyone else.

Post-mortem examinations were carried out this morning at Glan Clwyd Hospital by Dr Brian Rogers, a Home Office pathologist. Family liaison officers have been appointed to help Mrs Philcox and her family.

Teddy bears and bouquets of flowers were tied to the railings outside Mr Philcox’s single-story terraced home in Runcorn this afternoon. A police officer stood outside as forensics teams wearing blue gloves came in and out of the house.

It is believed that Mr Philcox, a karate expert, was chairman of the executive commitee of the British Federation of Karate Organisations.

His Land Rover Freelander, registration number W537 MNC, is being examined by forensic experts in St Asaph. Police appealed to anyone who had seen it since Saturday to come forward with information.

"Detectives are trying to establish a timeline of events which occurred before the three were found in the light-blue Land Rover on an unclassified road just off the A470 between Maenan and Tal-y-Cafn shortly before 3pm yesterday, Sunday, June 15," Mr Jones said.

Today two police cars continued to block the taped-off scene, believed to be in a passing spot on a single-track road, 500 yards from the nearest house.

A worker from a nearby bed and breakfast said: "The place where it happened is off one of the narrow roads crossing the country. It’s in the middle of fields with only a few houses near by, it’s very isolated. It is one of the prettiest parts of the country.

"I am more sorry for the children. I think it is a selfish act taking the children away."

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