DETECTIVES investigating a North-East murder have promised to go public about their progress on the 11th anniversary of the killing.

A series of new DNA tests have been carried out on exhibits collected during the investigation into the brutal murder of Ann Heron on August 3, 1990.

Police are still confident of achieving a breakthrough in the inquiry, and Superintendent John Blake, who is leading the investigation, will make an announcement on any updates next month.

A spokesman for Durham Police said: "Supt Blake is keen to give an update on progress on the anniversary of her death.

"At the moment we are not in a position to say anything more, except of course that the inquiry is continuing and we are hopeful of a breakthrough." The 44-year-old's bloodstained body was found at her home on the outskirts of Darlington by her husband Peter.

On the afternoon of her death she had been sun-bathing in the grounds of the couple's home.

Her killer slashed her throat in what detectives believe may have been a sexually motivated attack.

Police have been frustrated in all attempts to track down a sun-tanned man, aged 35 to 40, who was spotted driving a blue car at speed down the drive of the house at about 5pm, the time when Mrs Heron is thought to have been killed.

Anyone who can help police with their inquiries into Mrs Heron's murder can telephone 0191-386 4929 or (01325) 467681.

Updated: 15.50, Wednesday, July 11.