New DNA techniques are to be used in a fresh attempt to catch the killer of a 16-year-old schoolgirl who was stabbed to death in Kent 12 years ago.
The 16-year-old was stabbed more than 40 times in a random killing
Claire Tiltman was murdered in an alleyway in Greenhithe on 18 January 1993, while on her way to see a friend.
Nobody has been charged with her murder but Kent Police plan to review the case using forensic techniques which were not available at the time.
Claire's father Cliff said the news was "a step in the right direction".
Claire, a pupil at Dartford Grammar School for Girls, was stabbed more than 40 times, in an apparently motiveless attack four days after her 16th birthday.
The case is being reviewed by a team including a retired detective, and witnesses who were spoken to in 1993 have been interviewed again.
A Kent Police spokeswoman said: "As part of the regular case review process we are planning to send further exhibits from the Claire Tiltman murder investigation for forensic testing.
Claire's parents have been kept updated by police
"This will take some time to complete."
Claire was an only child and her parents still receive Christmas cards from her former schoolmates and teachers.
Her father Cliff said: "It's a step in the right direction, it's got to be.
"DNA is unbelievable, it progresses every month and what they couldn't do a year ago they can now. We've never given up hope."
Claire's mother Lin Tiltman added: "It's difficult, it really is difficult, obviously at this time of year with Claire's anniversary."
Speaking about the possibility of a new forensic breakthrough, she said: "I try not to get too excited, too emotional.
"I know if anything interesting comes up the police will be on the doorstep. At the end of the day it all takes time."
A memorial plaque to Claire was mounted on a wall on London Road in Greenhithe - the road leading to the alleyway where she was murdered.
Another plaque is on a bench in a memorial garden 100 yards from her parents' home, while a road on a new retail development in Greenhithe was named Claire Causeway in her memory in 2002.