Serial killer Peter Tobin has been convicted of a third murder - that of teenager Dinah McNicol 18 years ago.
Tobin, 63, from Johnstone, Renfrewshire, was found guilty of killing the 18-year-old sixth former after a three-day trial at Chelmsford Crown Court. The jury had deliberated for just 15 minutes.
Miss McNicol was the second young woman Tobin murdered in 1991 - 18 months after the break-up of his marriage. She vanished in August 1991 while hitchhiking to her home in Tillingham, Essex, after leaving a music festival in Liphook, Hampshire.
Six months earlier, Tobin had killed 15-year-old Vicky Hamilton of Redding, Stirlingshire.
But he was not caught until 2006, when he was arrested for killing Polish student Angelika Kluk, whose remains were hidden in a church in Glasgow where the handyman had worked.
After Tobin was found guilty of murdering Miss Kluk, police dug up the back garden at one of his former homes in Margate, Kent. There they discovered Vicky's body. Then Dinah's remains were found buried nearby four days later.
Both young women had been drugged. Forensic tests showed Vicky had been sexually assaulted and Dinah strangled with a ligature. Inquiries also revealed Tobin had plundered more than £2,000 from Miss McNicol's building society account.
Tobin, who denied murder, is serving life sentences for the murders of Vicky and Miss Kluk, a 23-year-old Polish student on holiday in the UK. The Chelmsford jury was not told about Miss Kluk's murder.
Judge Mr Justice Calvert-Smith will impose a life sentence later and recommend a minimum term.
Following the Hamilton trial in 2008 a judge ruled Tobin must serve 30 years before being considered for parole.
