Betty Yates murder: Police in fresh appeal for letter authors
Police hunting for the killer of Worcestershire pensioner Betty Yates have made a fresh appeal for the authors of two anonymous letters to come forward.
The letters, received last week, give different information and are believed to have come from separate sources.
Despite an appeal on Friday, the authors have not contacted detectives.
The 77-year-old retired teacher was found stabbed to death at her cottage near Bewdley on 4 January.
West Mercia Police said that the first letter was posted over the weekend of 14-15 January and was received on Monday 16 January at Bewdley Police Station.
The letter was printed, but the address on the envelope was handwritten.
The second letter arrived at the major incident room at Stourport Police Station on 18 January. It was also printed, but this time the envelope had a printed address on it.
An appeal for information will be broadcast on Crimewatch at 21:00 GMT on BBC1.
Det Ch Insp Neil Jamieson, who is leading the inquiry, said: "The letters have opened up new lines of enquiry for us but we can only establish the value of the details in them by talking to the people who wrote them.
"We need to find out how they came by that information and what else they know about this.
"It's crucial that anyone who has any idea of who was responsible for this terrible murder comes forward and gives us as much detail as possible."
Ms Yates had been beaten with her walking stick and stabbed in the neck.