Cold case detectives investigating the murder of a woman in Lancashire 35 years ago believe new forensic tests may give fresh leads.
The case of Joan Harrison, 26, from Preston, who was brutally murdered on 20 November 1975, was never closed.
Officers are awaiting the results of recent tests, which they believe will reveal fresh evidence.
Det Ch Sup Graham Gardner said officers were investigating "a new, interesting line of inquiry".
A police spokesman said: "Officers are awaiting the outcome of a report led by the Forensic Science Service - results they believe may be crucial to the investigation."