Police are looking for DNA matches in connection with one of Norfolk's most high profile cold cases.
On March 31, 2002, the body of then 22-year-old Michelle Bettles was discovered in woodland near to the A47 at Scarning.
To this day no convictions have been made in relation to her murder.
Investigators are now urging anyone who had personal contact with Michelle to come forward as they try and identify DNA profiles in connection with the case.
Michelle was a sex worker and was last seen in the red-light district of Norwich on Thursday, March 28, 2002.
She unusually had not kept an appointment with a regular client which she had arranged to meet close to her home address in the Dereham Road area of Norwich.
CCTV footage from the evening showed Michelle walking along St Benedict's Street towards the city centre at 8.20pm, suggesting she never intended to keep the appointment.
Her body was found three days later in Scarning woodland by the side of Rush Meadow Road.
A murder investigation was launched at the time but her killer was never identified.
Major Crime Review Manager, Andy Guy, said: “It is 20 years since the murder of Michelle and I do believe the public has vital information which can help us solve our investigation and give her family some closure.
“As part of a forensic review, we currently have items at the laboratory and seek to identify DNA profiles found in connection with Michelle.
"This has not been possible before so I would ask any person who had legitimate, personal contact with Michelle to come forward and be eliminated.
"Equally, we are eager to hear from anyone with useful information about the last few days of Michelle’s life.
“We know that Michelle had a number of acquaintances in Norwich and I am hoping that over time, situations or allegiances may have changed which will give someone the confidence to provide us with any new information which could be the key in solving Michelle’s murder.
“As part of the review, we are also looking at some information that suggests there was a potential sighting of Michelle in the City Road area, walking towards Queens Road just after 10.30pn on the evening of Thursday 28 March.
"There are also other uncorroborated sightings of her around The Rouen Road, Ber Street area."
Michelle's case is set to feature in BBC One series, We Are England, in which her father will return to Norfolk to retrace her steps.
On August 15 last year, on what would have been Michelle's 42nd birthday, her father John Bettles, 65, and mother Denise, 62, made an emotional return to Norwich to mark the heart-breaking anniversary.
Police are asking anyone with information to contact the Major Crime Review Team on 01953 423819 or email unsolvedcasereviews@norfolk.police.uk.
Alternatively, you can access the public portal via the website or can contact Crimestoppers anonymously on 0800 555 111.
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