Photo appeal to uncover serial killer Peter Tobin's past

Police today issued a fresh appeal for information about serial killer Peter Tobin as it emerged he used prostitutes and was a past member of biker gangs.

Last week, jurors at Chelmsford crown court took just 13 minutes to find the former church handyman guilty of strangling 18-year-old Dinah McNicol. He is already serving life terms for murdering Vicky Hamilton, 15, and Angelika Kluk, 23.

Police have gathered photos of Tobin, 63, of Johnstone, Renfrewshire, and are trawling through unsolved crimes to try to uncover the full extent of his past.

Det Supt David Swindle, of Strathclyde Police, told BBC's Crimewatch: "Information has been coming from various parts of the UK. His offences are horrific, without doubt he has probably committed more." He added: "People might not know him as Peter Tobin. They might know him by other aliases."

Police have also released photos of jewellery Tobin had in his possession. Mr Swindle said: "We know he had [it] in 1993 and in 2006. We want to know where he got that jewellery."

Miss McNicol was the second teenager Tobin murdered in 1991. She vanished while hitchhiking to home to Tillingham, Essex, after leaving a music festival in Hampshire. Her father Ian, 70, said: "That slim hope was always there. I never changed the lock just in case she would come back. But she never did."

Six months earlier, Miss Hamilton disappeared in Bathgate, West Lothian. Detectives focused on Tobin after he was convicted of killing Miss Kluk, a Polish student in Glasgow, in 2007. They found Miss Hamilton and Miss McNicol's remains in the garden of Tobin's house in Margate in March 1991.

Miss Hamilton's sister Lindsay said:

"Unfortunately I don't think Vicky was [Tobin's] first."

Mr Swindle said that there had been a "phenomenal response" to the appeal. He added: "I would appeal to people with any bit of information, any small piece, to log on to the website or phone." The photos can be found on www.bbc.co.uk/crimewatch