Melanie Hall's remains were found on Monday
A man who was arrested on suspicion of murder after the discovery of a woman's bones near the M5 has been ruled out as a suspect.
The 37-year-old went to Cheadle Heath police station, in Stockport, earlier, but Avon and Somerset Police said he had been eliminated from the inquiry.
The remains of Melanie Hall were found in a bin bag next to the M5 near Bristol on Monday.
Ms Hall went missing from a nightclub in Bath in June 1996.
Police have confirmed they are treating Ms Hall's death as murder.
Ms Hall's parents have spoken of their anguish at the way their daughter's body was dumped next to the motorway "like a bag of garbage".
'No real importance'
The man - who contacted Manchester Police at 0245 BST on Thursday - is being assessed at Stepping Hill Hospital in Stockport.
Avon and Somerset police travelled to Manchester to question the man, who is from the Hazel Grove area of Stockport.
Speaking from his home in Bradford-on-Avon, Wiltshire, Melanie's father Steve Hall said: "We are not really attaching any real importance to the arrest.
"On numerous occasions over the past 13 years we have had people come forward and confess and I think this is probably one of those occasions."
Police say they have received 75-100 calls regarding the murder hunt since Thursday, when they held a press conference on the case.
Detailed forensic investigations are still continuing in a bid to establish the precise cause of death and in an attempt to find any additional evidence which can help the inquiry.
Anyone with any information is being urged to contact the incident room on 0845 456 7000.