A FORMER shopworker has come forward to tell of the day a sales rep said he was guilty of committing one of County Durham's most notorious murders.

The 64-year-old woman, who asked only for her first name of Sylvia to be used, said she was working in a card shop in Newton Aycliffe in late 1992 or early 1993 when a man came in bragging that he had murdered Ann Heron in Darlington in 1990.

She insists that, apart from a brief conservation with a police officer, Durham Police never followed up her claims, although Durham Police say the information she provided was acted on.

The killing of Ann Heron, who was 44, at Aeolian House, a large detached home on the outskirts of Darlington, is County Durham's only unsolved murder. The mother-of-three had her throat cut and her body was was found by her husband, Peter Heron on August 3, 1990.

A spokeswoman for Durham Police insisted that in fact a detective did speak to her, although Sylvia says she only spoke briefly to a police officer and was expecting a return call which never came.

Sylvia, who was working in a shop called Card Market in the main town centre square in Newton Aycliffe, said: "The manageress took him to the back to talk about possible orders.

"They were gone about ten minutes and he came out first. He looked at me and smiled, although it was more a smirk than a smile.

"The manageress came behind and she was physically shaking. She was frightened. She said, 'you'll never believe what he told me.' He had told her that he had killed Ann Heron but he was never going to be caught because he was moving to Australia.

"I don't know why he said it, although the manageress looked a lot like Ann Heron.

"She wouldn't go to the police saying he was probably just 'playing silly beggars.' It was only years later that I read about the murder and it really shook me because the description was exactly the same as that of a man seen speeding off in a car from the house.

"Swarthy, dark, early 30s, it was exactly the same. I know it is just hearsay but I think the police should have at least interviewed me properly."

Sylvia said that her former boss had since died.

Peter Heron, who was charged with the murder in 2005 although the case against him collapsed, thanked Sylvia for coming forward and said: "Durham Police must not be allowed to get away with ignoring evidence from key witnesses."

A Durham Police spokeswoman said Sylvia did not contact police until 2010 and added: "Despite the age of the information it was passed to the Major Crime Team and she was spoken to by a detective and the information she provided acted upon."

The Northern Echo was sent a letter by a man claiming to be the murderer in 1994 which was passed on to police.