Mike Britton has interviewed thousands of witnesses during the 13-year inquiry
A detective who worked on the original investigation into the murder of a woman 13 years ago will stay on after retirement until her killer is caught.
Former Det Sgt Mike Britton formally retired on Friday, but will return to work as a civilian to work on the ongoing Melanie Hall investigation.
Ms Hall went missing after a night out in Bath, Somerset. Her bones were found beside the M5 motorway on 5 October.
"This is for me now, more than ever, a case I want solved," he said.
'Family deserve it'
Ms Hall, 25, from Bradford Leigh in Wiltshire, was last seen at a Bath nightclub in 1996.
Her bones were discovered close to the M5 near Thornbury in South Gloucestershire.
And after 13 years working on the same case, Mr Britton says retirement is not an option now that remains have been found.
He said: "It's not for me, it's for the family and I think they deserve that.
"I just felt I needed to be here. I wanted to be here because I have been involved with this investigation throughout.
"This is why you join the job. This is what you want to be part of."
Police say they have taken more than 200 calls since the murder inquiry was renewed after the discovery of Ms Hall's remains.
Despite several searches by police, no trace of the Royal United Hospital clerical worker was ever found until workmen clearing away vegetation discovered her remains.
Anyone with information has been asked to ring the murder incident room on 0117 9455811 or call Crimestoppers.