Glasgow woman Ann Heron was brutally murdered in her own home 32 years ago this month.
She was 44-years-old at the time of her death, and it sparked a media frenzy, subsequently featuring on Crimewatch.
Ann's killer has never been found and a new Channel Five documentary released this year has renewed interest in the case, which has puzzled many for years reports the Scottish Daily Express.
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Ann Heron, born Mary Ann O'Neill, was born in Glasgow on March 24, 1946. Her first marriage was to a man named Ralph Cockburn, with whom she had three children with before their marriage broke down and she moved down to England at some point in the 80s.
Ann had left her children in Glasgow and in 1986 she began a relationship with married Peter Heron, a company director for a haulage firm.
Peter divorced his wife and the couple married in the same year. They moved in together in a house on the outskirts of Darlington, County Durham, with Ann getting a part-time job as a care assistant at a local care home.
Ann was unhappy in England, and missed her children who were still in Scotland. She was also known to feel frightened by her home, Aeolian House, which was a conspicuous building on the main road to the airport. She was known to not want to be alone in the building.
On August 3, 1990, it seemed like a normal day except for the heatwave across the north east of England and so Ann said she would spend the day sunbathing in her bikini while her husband went shopping with a friend, before returning for lunch.
Peter was back at work by 2pm and at around 2.30pm, Ann spoke to a friend on the phone and was reportedly in a good mood. She was spotted sunbathing at 3.30pm at the front of the house where she had moved to avoid grass being blown into the back from a nearby tractor. It was the last known sighting of Ann alive.
Ann was found in the living room lying in a pool of blood with a stab wound to her neck. Her bikini bottoms had been removed which led police to believe the killing may have been sexually motivated.
Peter had arrived back from work at 6pm to find the radio still on while the family dog, Ann's book and cigarettes were all outside. The front door was open.
The murder weapon has never been found but is believed to have been a Stanley knife or razor blade.
There was no sign of a struggle or forced entry, indicating she may have known her killer. The family dog had not been heard to bark to signal an intruder and there was no sign of robbery or sexual assault.
Several witnesses came forward to say they had seen a blue car or van parked near to or outside the house around 4.45pm. A taxi driver reported a blue car speeding away from the scene at around 5pm - the time police believe Ann was killed.
The driver was described as being between 35 and 45 with a suntanned complexion and short, dark hair. Despite tracking down the owners of 3,500 blue cars, the vehicle - believed to be an Astra, although several other makes were possible - has never been found. A photofit was never produced by Durham Constabulary despite the witness descriptions.
By 1991 the case had gone cold although one woman told police someone at a card shop she worked in had boasted of killing Ann and the local paper, police and Peter Heron were sent letters claiming to be from the murderer.
The initial suspect was Peter Heron. One witness claimed they seen him driving near the house at around 4.15pm with two unidentified persons, but they were not certain.
It was later discovered Heron, who was 55 at the time, was having an affair and he remarried in 1992 in a ceremony attended by uniformed police officers. He moved to Wishaw and he was arrested in 2005 after Durham Constabulary brought in a forensic expert to go over the evidence again. All charges were subsequently dropped due to a lack of evidence.
The Heron family have been highly critical of the police investigation and made as formal complaint. Daughter, Debbie Simpson, told The Northern Echo: "His family and true friends knew from the moment of his arrest that a terrible mistake had been made and now, after being in possession of the prosecution bundle of evidence against him for over 16 years, we believe we have finally uncovered the truth of the circumstances which led to his arrest and have made a formal complaint.
“Since the moment of Dad’s arrest, I have fought relentlessly to keep Ann’s case alive and in the public eye in the hope that one day, Durham Constabulary would find her real killer and Dad’s name would be cleared; a hope sadly not shared by some.
"In the face of mounting evidence to the contrary and increasing public knowledge and awareness of the facts, it is inhumane that at the age of 87, Dad continues to live with the finger of suspicion hanging firmly over him through the actions and failures of others.”
Despite that, according to the Channel Five documentary, The Mysterious Murder of Ann Heron, released in May this year, Peter Heron remains a suspect.
Other suspects included a convicted rapist and murderer and a man named Michael Benson, who died in 2011. However, police eventually concluded he was likely out of the country at the time of the killing.
To this day, Ann's killer has never been found. The Mysterious Murder of Ann Heron can still be viewed on My5.
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