ADVANCES in forensic science could finally reveal who killed a Scottish schoolgirl 20 years ago, it is claimed. The body of Caroline Glachan, 14, was found on the banks of the River Leven, just one mile from her home in Renton, West Dunbartonshire, in 1996.

The teenager was last seen heading to meet her boyfriend after spending the evening with friends.

Police issued a description of a male seen running through the streets shortly after Glachan left her friends, but no-one has ever come forward and no arrests have been made in connection with the murder.

Glachan was killed as her mother, Margaret McKeich, celebrated her 40th birthday on August 25, 1996. McKeich has made repeated public appeals for information. Yesterday, she begged the public to help find the killer and end her wait for answers as police launched a fresh inquiry.

Part of the work will involve fresh DNA sampling of articles recovered from the river. Until now, experts have been unable to interpret information taken from the items, but it is hoped that scientific advances will now reveal fresh clues.

McKeich, who previously said solving the case was the last thing she could do for her daughter, said: “I’ve been here before and it’s 20 years down the line. What can I say that I haven’t said before? What can I do that I’ve not done before?

“I’m a wee bit more hopeful than I’ve been for a long time. The public have a part to play in this as well and I’d urge anybody to come forward to give me that peace, to let Caroline rest in peace and to give me closure. There are two questions I need to answer – who and why?”

McKeich, who believes her daughter was attacked by someone she knew, added: “Twenty years has passed and it’s a fair amount of time, but for me it’s just yesterday. Twenty years is long enough. Just let this year be the last year.”

The 60-year-old was speaking at Bonhill Community Centre on the Ladyton estate, just yards from where Caroline was last seen. Her body was recovered from the edge of the river near a primary school by a passer-by. She was fully clothed but her shoes had been removed.

Ten years ago, a local business offered a four-figure sum for inform- ation leading to the killer's arrest and conviction 10 years ago. It has yet to be claimed.

Friend Joanne Menzies, thought to be one of the last people to see

Caroline alive, appealed to the community, saying: “There are people who know who did it, who are shielding whoever did it, and I would ask these people to come forward now.”

The case will feature on the BBC’s Crimewatch programme on Monday. Forensic scientist Amanda Pirie, of the Scottish Police Authority, said new samples could be retrieved from evidence taken from the water.

She said: “All of this combined will enable the cold case team potentially to recover and detect trace amounts of DNA which will hopefully enable us to identify individuals with whom, for instance, Caroline Glachan may have been in contact at or around the time of her death.”

Detective Superintendent Jim Kerr said DNA testing is “on a different planet” compared to 1996, adding: “I feel as if this is a black cloud over Renton and Bonhill and we need to get it lifted.”