Detectives today hailed a forensic breakthrough which has put them closer to catching the brutal killer of a teenage mum - seven years after her murder.

Rebecca Hall, known as Becky, went missing on April 13, 2001.

Her battered body was found dumped in an alleyway in Bradford's red light district two weeks later. Detectives have studied more than 300 DNA profiles of potential suspects since.

But last night the police chief leading the murder inquiry revealed that advances in DNA technology had raised hopes of identifying the killer.

DNA samples, recovered from items of Becky's clothes at the time, are being examined by forensic scientists using the latest technology, and detectives believe it will enable them to identify the man responsible more easily.

Detective Chief Superintendent Max McLean said DNA had been found on a strap top and knickers which had been ripped from the 19-year-old's body at the time of her murder. At the time the samples had been insufficient to identify an individual.

But Det Chief Supt McLean said: "We are working closely with the Forensic Science Service to develop that profile into something more meaningful, something that would identify the person responsible.

"We are encouraged by other examples of cold case review investigations where DNA technology has moved on, allowing subsequent identification of a suspect.

"We have got profiles from these items of Becky's clothing. It genuinely gives us hope we will catch Becky's killer. I believe in my heart that we will get him through the DNA."

Becky, who worked as a prostitute to pay for her heroin addiction, was last seen alive when she left her flat at Lydford House, in Elizabeth Street, Little Horton, at about 10pm on April 13 - which was Good Friday.

Her naked body was found behind a car park in Thornton Street.

The teenager, who had a four month-old baby boy, had been stripped and subjected to a "sustained, vicious and brutal beating" and died from severe head injuries.

Detectives continue to believe Becky is likely to have been killed by a "punter" who lived locally.

Det Chief Supt McLean admitted the public response to the murder had been disappointing over the years, but insisted someone in Bradford must know the identity of the murderer.

He said: "People tend not to come forward with information when a prostitute is murdered. Some may even see it as a hazard of the job.

"But we need to remind people that this was a 19-year-old girl - a mother, sister and daughter who was much loved - who was brutally beaten to death and her killer badly needs to be caught.

"I believe someone in Bradford knows who is responsible. I believe this is a local murder. I suspect the killer knew Becky or regularly used her as a prostitute.

"She is loved and missed greatly by her family and the best thing they could wish for is for her killer to be found so they can finally have some closure to their terrible loss."

Becky was 5ft 5ins tall, slim, with dyed red hair cut in a bob-style. She was last seen wearing black leggings and a purple sheer top. Her knee-length black boots, Motorola Star Tac mobile phone and a distinctive limited edition watch with a South Park cartoon character have never been found.

Anyone with information about her murder should contact West Yorkshire Police's Homicide Review Team on (01924) 292456.