Nearly 18 months on, Ms Jones's killer remains at large
The Royal Thai Police announced a new inquiry into the death of backpacker Kirsty Jones within hours of receiving new forensic evidence from Dyfed-Powys Police last week.
The 23-year-old farmer's daughter from Tredomen in mid Wales was raped and strangled at the £1-a-night Aree guesthouse in Chiang Mai in August 2000.
The DNA evidence presented by two Dyfed-Powys officers to their counterparts in Bangkok has revealed that the rapist was definitely Asian, and they have called on the Royal Thai Police to test some of their own officers.
Ms Jones, a Liverpool University graduate, had been travelling alone and was just a few months into a two-year round-world trip.
The handling of the initial investigation was widely criticised and UK officers became involved a few months later.
The inquiry by officers in Chiang Mai was branded a shambles after journalists and junior policemen were allowed to trample over the murder scene, contaminating forensic evidence.
But clothing and bedding from the hostel room was brought back to the UK in an attempt to discover undisturbed DNA evidence after Miss Jones's parents asked for the Welsh force's help.
Those tests have confirmed the killer is Asian and suggests he may be from a particular Thai hill tribe.
Andrew Chant is a British journalist in Thailand who has been following the case.
He told BBC Wales: "The DNA showed that it was without doubt an Asian and it made a close match to a tour guide.
"What the British police told the Thai police was firstly to reopen the case and to start looking at the family of the tour guide and spread the net.
"It's possible and now indeed likely that it's not the family of the tour guide.
"They've also asked the police to test their own members of the tourist police in Chiang Mai.
"It seems to tie-in with the fact that early on in the case the investigation was described as a shambles and seemed to be going nowhere and the police closed it down as quickly as they could.
"If it does turn out to be a policeman, it would explain why the investigation came to such a quick halt."
Dyfed-Powys Police has declined to comment on the case until the two officers involved, Superintendent Steve Wilkins and Detective Inspector Steve Hughson, return to the UK on 14 or 15 January.
In the initial investigations into Miss Jones's killing, Thai police arrested the hostel owner Andrew Gill, 33, after releasing a number of other suspects.
He was originally questioned over passport irregularities.
Specific individual
But the former ski instructor from Lewisham in south London, vehemently denied the accusation and was later released without charge.
DNA tests ruled out a further 11 suspects.
Dyfed-Powys Police has issued a statement denying that its DNA evidence linked the murder to a specific individual.
"Whilst in Thailand, officers from Dyfed-Powys Police have had a number of discussions with and presentations to the Royal Thai Police.
"The discussions have included the results of forensic analysis which took place in the UK.
"A number of lines of enquiry were identified.
"However, Dyfed-Powys Police do not want to make comment on the details of those enquiries."