THE husband of a mother-of-three, whose killing led to one of the region's longest-running investigations, was charged with her murder last night.

Retired businessman Peter Heron, 70, is accused of the murder of his wife, Ann, whose throat was cut at their home on the outskirts of Darlington 15 years ago.

The former company director is being remanded in custody at Spennymoor police station.

A spokesman for Durham Constabulary said last night: "A man has been accused of the killing of County Durham housewife Ann Heron. Shortly after 9.30pm, Peter Heron, the husband of the victim, was formally charged with her murder."

A team of six officers arrested Mr Heron after an early morning raid on his bungalow in the Motherwell area of North Lanarkshire, Scotland, on Wednesday.

He was brought back to the North-East and interviewed at Spennymoor police station.

Despite the age of the case, the man leading the investigation, Detective Superintendent Dave Jones, has renewed his appeal for anyone with information to come forward.

Mrs Heron was 44 when her body was found at her home, Aeolian House, near Middleton St George, on August 3, 1990.

The murder sparked one of the largest investigations undertaken by Durham Constabulary and senior officers remained adamant that her killer would be brought to justice.

Det Supt Jones previously said: "We do remain absolutely determined to bring the person responsible to justice. As far as we are concerned, this case has never gone cold."

The development comes four months after police revealed to The Northern Echo that technological advances could bring them closer than ever to catching the killer.

The force called in one of the country's foremost forensic experts to lead a series of laboratory tests.

It was hoped that breakthroughs in technology would allow the expert - who has not been identified - to examine samples from the murder scene, which are so small that, until now, they have been beyond scientific analysis.

More than 1,500 items were taken from the crime scene and forensic scientists have re-examined a small number of them for minute clues.

A report by retired detective Ian Phillips, who was brought in last year to lead a "cold case" review of the murder, has also been completed.

As part of his review, Mr Phillips read 4,400 statements, examined 1,500 samples and looked at files on more than 7,000 people who were questioned.

The documents associated with the case are estimated to weigh a quarter of a tonne.

Mrs Heron was attacked as she sunbathed in her garden on the hottest day of the summer.

She had not been sexually assaulted, although her bikini bottoms were missing.

The Heron case is one of only two unsolved murders in County Durham. The other is that of May Rebecca Thompson, who was killed in Spennymoor in 1952. The case is still being investigated.

Mr Heron will appear before Newton Aycliffe Magistrates' Court today.

* Anyone with information is asked to call police on 0845 60 60 365, or Crimestoppers on 0800 555 111.