AMATEUR sleuths with an interest in past crimes could be the key to solving decades-old murders, a researcher has claimed.

Neil Robinson said public fascination with grizzly crimes such as the Moors Murders could help re-invigorate cold cases.

Mr Robinson, who has interviewed cold case detectives, including officers at GMP, claims armchair sleuths who review archive evidence on the internet could provide invaluable insights into cases.

He teaches a course in `dark tourism' at Salford University, where students discuss why increasing numbers of people visit sites such as Chernobyl, Auschwitz and Middle Eastern trouble-spots.

The tourism and management lecturer cited a number of US cases where a dedicated group of internet sleuths had managed to uncover the identity of dozens of unidentified bodies.

The most celebrated instance was the Tent Girl case, where a Kentucky woman whose remains were found in 1968 was identified 30 years later by an amateur who combed missing person reports on the internet.

Neil said: "People have been visiting sites associated with death and murder for centuries - mass murders happened in places such as the Roman Coliseum and Jack the Ripper tours have been popular for several years now.

"By tapping into tourists' motivation for experiencing authentic and real situations - coupled with the continued fascination for solving crime - the `cold case investigation' offers an opportunity for individuals to possibly reinvestigate those."

The researcher said he drew the line at ghoulish visitors who made pilgrimages to the homes of Gloucester serial killers Fred and Rose West and criticised recent Madeleine McCann coach tours to the Portuguese town of Praia da Luz where the little girl disappeared two years ago.

But he admitted there was a fine line between well-meaning sleuthing and `ghoulish' interest in macabre cases.

He said: "Obviously a lot of the reports from the public must be treated with extreme caution by the authorities.

"Due to the sensitivity of the various crimes, particularly if they are relatively recent and if family members are still alive, then certain types of behaviour should not be encouraged.

"In the case of the Moors Murders, there are still surviving relatives but there are unsolved questions about the case, there has to be a balance.

"However, police themselves say there is no reason why well-meaning amateurs and access to material on the internet cannot spot vital clues."