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 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 next month on any updates.

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

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 seen driving a blue car at speed along the drive of the house at about 5pm, the time when Mrs Heron is thought to have been killed.

Anyone with information can call 0191-386 4929 or (01325) 467681.