POLICE said today the death of missing mum Jane Payne was not being treated as suspicious but how she spent her final hours remains a mystery.

The body of the some-time prostitute was discovered in the Thursden Valley last month and detectives are probing how she came to end up in the remote spot.

Insp Dave Hickey, the man leading the team of detectives investigating the death, said: "Preliminary toxicology findings have been reported and these have been made available to the Home Office pathologist to assist in establishing cause of death.

"The death is not being treated as suspicious and a file of evidence is being prepared for the coroner.

"We are still, however, keen to establish the circumstances leading up to the discovery of Jane's body in Thursden Valley and would once again appeal to anyone with information."

He added: "It is not a murder investigation. However, there are clearly aspects of the discovery of Jane's body which need to be resolved.

"Once we know that we can decide what, if any, further action needs to be taken and we can let Jane's family know the exact circumstances leading up to the discovery of her body."

Officers have been working on the theory either that Jane, a known drug user, died accidentally, perhaps from an overdose, and was taken to the site, or went to Thursden Valley with a client and died at the spot.

Officers have already turned to fellow sex workers and kerb crawlers for help and Jane's family have offered a reward for information about the death.

The mum-of-one, 29, went missing from her home in Queen Victoria Road, Duke Bar, at the end of March.

A post mortem examination has proved inconclusive, although there were no signs of violence on the body.

An inquest has been opened and adjourned.

Police said Jane, who has connections to Burnley and Nelson, would work as a street vice-girl when she was short of cash.