Cold Case: 50 years since murder of Norfolk teenager Susan Long

Detectives looking at the murder of a teenager in Norfolk 50 years ago say they have a complete DNA profile of the suspect as they make an anniversary appeal.

Susan Long was found on Burgh Road a mile from Aylsham Market Place on March 11 1970 by a local milkman at 5.15am. She'd been strangled and sexually assaulted.

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On the evening before the 18-year-old went on a night out in Norwich with her boyfriend to the Gala Dance Hall.

She left at about 10.25pm to catch the bus back to Aylsham. The bus arrived in Aylsham Market Place at 11.10pm. It has always been assumed she got off the bus there, but no one actually witnessed her getting off, according to police.

Detectives believe that Susan was driven to where her body was found, but officers do not know if she went voluntarily or was abducted.

Forensic evidence has established that the offender was from a rare blood group and blood samples were taken from men living in the Aylsham area.

The case has been periodically reviewed ever since with anniversary appeals providing new lines of enquiry which have been investigated.

Since 2003, officers and staff have been researching DNA comparisons and DNA familial work.

Then in 2010 a new line of enquiry was established with DNA familial comparisons, but despite this extensive work, the offender has still not been identified.