Appeal: Jonathan Jones with his wife Cheryl

Their bodies were then wrapped in carpets and hidden in a cowshed at their smallholding in Llanharry, outside Cardiff.

Jonathan Jones - the boyfriend of the Tooze's daughter Cheryl - was wrongly convicted and jailed for life in 1995.

Cheryl Tooze, now married to Mr Jones, mounted a campaign to prove his innocence and after spending two-and-a-half years in jail, the 40-year-old's conviction was quashed.

On Thursday, South Wales Police announced that a new team of detectives have been brought in and fresh lines of inquiry have been identified after an independent review of the original inquiry by a lay panel.

As well as pin-pointing specific areas of concern in the initial Tooze murder inquiry, the panel also recommends several changes to the way in which the force investigates murders

I believe this case is still solvable and we would appeal for anyone with information to come forward

South Wales Police Assistant Chief Constable, Tony Rogers

Despite the time lapse of eight years, Assistant Chief Constable Tony Rogers said: "I believe this case is still solvable and we would appeal for anyone with information to come forward.

"As this is now a live investigation and so as not to jeopardise any active lines of inquiry I can not make any further comment."

The initial murder inquiry had been the subject of a review by an Independent Advisory Group - a controversial approach but one being considered by a growing number of forces.

Comprising of members of the public from a variety of backgrounds, the group's aim is to scrutinise the inquiry and make recommendations.

It is the third time South Wales Police chose to involve civilians in such a way - the first case being the unsolved murder of Cardiff prostitute Lynette White in 1988.

It is the third time the force employed a lay panel

In its report, the panel made recommendations specific to the Tooze inquiry as well as general changes to the way in which the force investigates murders.

"The review report contains recommendations that are separated into two areas, Mr Rogers explained.

"The first deals with the procedures and practices around homicide investigations generally.

"The second area of recommendations deals specifically with potential inquiries into Harry and Megan's murder.

"As a result Chief Constable Tony Burden has instructed that the recommended lines of inquiry be pursued by a newly formed team of investigators."

Meanwhile Mr Jones - who has since set up home with Cheryl in Caerphilly where they have begun a family - is still pursuing complaints against the police.

He is calling for a public inquiry into the conduct of South Wales Police, and has dismissed the panels as "window dressing".