Detectives investigating the murder of Melanie Hall 20 years ago have received "potentially significant information" following an appeal.
More than 20 calls made after a BBC Crimewatch programme are being followed up by police.
Ms Hall, a 25-year-old university graduate, was last seen at 1.10am on 9 June 1996 sitting on a stool on the edge of the dance floor at Cadillacs nightclub in Bath.
A workman found her remains in a bag in vegetation next to the northbound slipway of junction 14 on the M5 at Thornbury on 5 October2009.
Avon and Somerset Police now have DNA evidence from an item found at the scene where Ms Hall's remains were discovered.
Melanie was wearing earrings similar to these when she was killed
Detective Superintendent Andy Bevan said: "We have officers and staff following up on information we've received following the Crimewatch Roadshow appeal yesterday.
"Some of the calls provided names of potential suspects, some related to the outstanding items of Melanie's property which have never been found, and others were reporting suspicious activity around the motorway slipway where Melanie's remains were found.
"We're extremely grateful to everyone who has responded so far but we still need more information from the public.
Police say some of the latest calls have named potential suspects
"I firmly believe someone out there knows who killed Melanie and now is the time for them to come forward to bring some relief to her family, who've been through 20 years of heartache."
Mr Bevan said police were working with forensic scientists to develop the DNA into a profile.
"I believe this brings us a significant step closer to finding Melanie's killer," he added.
The force does not have a prime suspect or any conclusive evidence that Ms Hall's death is linked to other murders or sexual offences.
Nine people have been arrested in connection with the case since the investigation began, but no-one has been charged.
Officers are asking for sightings of Ms Hall after she left the nightclub, and for witnesses to any suspicious activity or a vehicle parked near where Ms Hall's remains were found.
Her clothing and belongings have never been found, including her pale silk dress, black suede mule shoes, cream jacket and handbag.
Melanie's body was found near the M5 motorway
Her parents Steve and Pat Hall have pleaded for anyone with information about their daughter's death to come forward.
"There are a number of people there and we just need one of them to come forward with that key bit of information," Mr Hall said.
Melanie's parents have joined the appeal for new information
Crimestoppers is offering a £10,000 reward for information leading to the arrest and conviction of those responsible for Ms Hall's murder.