Mrs Philcox alerted the police after her husband did not return with the children on Saturday, as he had promised.

Friends yesterday said the couple were going through a difficult divorce, which had caused rows at the family home.

Mr Philcox was chairman of the Federation of English Karate Organisations (FEKO) and the group’s honorary secretary Alan Carruthers said he seemed positive last week, when the pair last spoke.

Mr Carruthers, who had known Mr Philcox for 20 years, said the karate expert had been told he could not look after Amy and Owen on Father’s Day: “He certainly loved his children – I spoke to him last week and he was quite positive about things.

“There was an up-coming court case about the ownership of the house, but it appeared to be getting sorted out.

“Another friend of mine spoke to him yesterday (Sunday) and said Brian had asked for the children on Father’s Day and he was refused, so whether that is something to do with it I don’t know.

“We were all totally shocked. From the outside he was a very nice chap, greatly respected as a person and a martial artist.

“I can’t imagine what has taken him over the edge, it seemed like problems were being resolved.

“He and Lyn were married about eight years ago, his previous wife had died of cancer.

“He was an extremely nice person.”

Lobby group Fathers 4 Justice (F4J) have confirmed Mr Philcox had been in touch with them, but that their database showed that he had not joined the group.

The group say the father had called on several occasions and had been advised to join the group via their internet site to get help, support and advice, but that he had not done this.

F4J Founder Matt O'Connor said: “This is yet another tragic case that demonstrates how family breakdown is an unfolding national tragedy for families and children.

“Fathers love their children.

“Killing them is against the paternal instinct, but while some people are driven to scaling bridges out of desperation, others see a future so bleak, and fear the living bereavement of losing their children so much, that they turn away from hope.”

Police reveal details of tragic scene

POLICE have revealed the poisonous car exhaust fumes which killed Brian Philcox and his young son and daughter were fed into the Land Rover by a hosepipe.

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

Mr Philcox, Amy, seven and Owen, three, were found in the vehicle by a passer-by at 3pm on Sunday.

He said they were found sitting in the rear seat of the vehicle and a hosepipe was linked from the exhaust into the car through the back window.

Mr Jones said there were no signs of violence on the children, and toxicology tests were being carried out, but the results may not be known for several weeks.

He added: “There is nothing to suggest that he would have done anything to harm the children when he picked them up from their mother’s house on Friday night.”

He said there were no letters written by Mr Philcox found in the Land Rover.

Mr Jones also confirmed that a bomb disposal unit was called to check out the vehicle after Cheshire police officers found a “device” at the family’s home on Lockgate East, in the Windmill Hill area of Runcorn, which proved to be a hoax.

Superintendent Jed Manley, of Cheshire Constabulary, said: “It was made to give the appearance of being an explosive device. It has wires. It had other issues and the officer believed, quite rightly, that caution was needed and it looked like an improvised explosive device.”

Mr Manley said Mr Philcox also had other children with other partners.

He said: “The only two children he had with his current wife were the children he had with him when his body was found. He does have children from previous relationships and a wider family.”

Speaking of how the two children’s mother was coping, Mr Jones said: “Obviously, as the mother of the children who were killed, she is devastated, she has suffered this double loss.

“She is being looked after by family liaison officers who are giving her comfort and support at this time, and she does have a good network of family and friends around her, but obviously this is a tragic loss that she’s suffered.”

Mr Philcox, of Runcorn, had picked up Amy and Owen for an arranged access visit on Friday.

The children had been due to be returned to the mother’s home in Runcorn on Saturday night.

When they did not appear they were reported missing, and police in Cheshire had been looking for them.

There had been a sighting of the three at Llangollen on Saturday, and they had visited the steam railway in the town.

Mr Jones said police were unaware of any links Mr Philcox may have had with North Wales, and believed he may have chosen the road at Maenan “at random”.

Later, a witness saw the vehicle parked on the road.

“A man answering Mr Philcox’s description was smoking in the front seat of the vehicle. Everything seemed normal and there was no cause for concern at that stage,” he said.

Mr Jones said police inquiries are continuing and appealed to anyone who saw Mr Philcox’s Land Rover Freelander between 7pm on Friday evening and just before 3pm on Sunday to contact officers at North Wales Police.

He said: “The investigation into the incident continues.

“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 on Sunday, June 15.”

The 4x4 Land Rover Freelander's registration number is W537 MNC.

Anyone with information about the incident should contact police on 0845 607 1002 or Crimestoppers, anonymously, on 0800 555111.

lizawilliams@dailypost.co.uk