The stabbing of an off-duty Met Police Officer, a banker shot on his doorstep in Scotland, and a woman found bludgeoned to death in Doncaster are among the shocking cases which have never been solved.
The victims range in age from missing 14-year-old Sarah Benford who is believed to have been murdered, to 69-year-old Nora Tait.
Among the unsolved murders are that of Alistair Wilson who was shot dead on his doorstep in Nairn in 2004
Meanwhile, the killer of DC Jim Morrison is still at large. The off-duty cop was stabbed in Covent Garden, London, in 1991 while trying to apprehend a suspected thief.
Police have continued to hunt for those responsible for the murders in order to get justice for the victims and their loved ones.
Here are some of the most shocking unsolved murder cases from the past four decades.
1. DC Jim Morrison
Met Police officer DC Jim Morrison, 26, was off-duty when he was stabbed in Montreal Place, Covent Garden on 13 December 1991, following a struggle with a man he was trying to arrest for a suspected bag theft. On the night of the incident he had gone to the Nell Gwynne pub at Bull Inn Court for around an hour from 8pm, before deciding to head home. However, a group of at least three bag snatchers had recently been working in the area to steal women’s’ purses and handbags - and that night a handbag had been stolen from the Maple Leaf pub in Maiden Lane. Jim was seen involved in a struggle with a man outside the London Transport Museum shortly after 10pm. At the time of the attack the suspect was described as being of Algerian or North African appearance, 5ft 10 inches tall and aged approximately 27 to 30. He was of medium build, clean shaven and had dark collar length hair, with distinctive tight curls at the front. He was wearing a waist length tan/brown leather jacket.
2. Barry Rubery
Barry Rubery, 68, was killed after returning to his home in Iron Acton at about 10.45pm on Wednesday 28 April 2010, shortly after he returned from a night out. He was found in his porch at 8am the following day by a friend. His wrists had been bound together with large, white cable ties and then tied to his ankles. There was clear evidence of a struggle in his back garden. A post-mortem examination later confirmed he’d suffered fatal head injuries sustained in a violent assault.
Although drawers had been emptied and the loft disturbed, very little from the house was taken apart from Barry’s Nokia 3310 and a set of keys. Items of value were left behind, including cash, jewellery and the safe. Barry’s case featured on a BBC documentary earlier this year.
3. Michelle Bettles
Michelle Bettles was 22 years old when she was murdered. She operated as a street prostitute and was last seen in the red light district of Norwich during the early hours of Thursday 28 and Friday 29 March 2002 Easter weekend. Unusually she had not kept a pre-arranged appointment with a regular client of hers. They had arranged to meet close to her home address. CCTV footage shows Michelle walking along St Benedict’s Street towards the city centre at 8.20 pm that night. Clearly, for whatever reason, she had never intended to keep the appointment with the regular client since she was heading in the opposite direction to their meeting. There was a series of sightings of Michelle in various locations in the red light district of Norwich by people that knew her, the last being at about midnight. On the morning of 31 March 2002, Michelle’s body was found in woodland by the side of a country track known as Rush Meadow Road in Scarning, near Dereham - around 20 miles from Norwich’s Red Light district. She had been strangled.
4. Alistair Wilson
Scottish banker Alistair Wilson was gunned down on his own doorstep in 2004.
Around 7pm on Sunday, 28 November, a man called at the family home in Nairn, and spoke to Alistair’s wife Veronica who answered the door and asked for “Alistair Wilson”.
Mr Wilson, 30, went downstairs to speak to the man and was handed a blue envelope with the word “Paul” on it. He went inside briefly and then returned to the door for a second time when he was fatally shot.
No one has been apprehended over Mr Wilson’s murder. The gun was recovered from a drain nearby days later.
In March this year police travelled to Canada to carry out witness interviews in Nova Scotia. Recently they said they believed the answer to his murder lies in his personal life rather than his professional one. They appealed for information about a planning application for decking outside a hotel opposite his home which he had objected to shortly before his death. Police have also called for anyone who had been in the Havelock Hotel two days before the shooting. Officers believe the objection was discussed in the hotel bar on Friday, 26 November, 2004, and over the weekend up until Mr Wilson’s murder on the Sunday night.