A man has been arrested over the “brutal” stabbing of an 83-year-old dog walker.
The body of Peter Wrighton was found three miles south of East Harling in Norfolk on 5 August.
He had been repeatedly stabbed in his neck and head, post-mortem examination tests showed.
Norfolk Police has arrested a local man, in his 20s, on suspicion of murder and he remains in custody while inquiries continue.
Mr Wrighton’s body was found near to Fiveways Junction at about 10:45 BST. His dogs, Dylan and Gemma, were found close by.
On Friday, police said they had traced one of three “vital” potential witnesses – a man in his 50s seen changing into a T-shirt – but they said they still wanted to speak to two other men.
One is aged 25 to 30, with tanned skin, was was wearing a grey or blue t-shirt, grey gym shorts and heavy-duty flip flops. The other, aged 30 to 50, was wearing dark clothing and seen walking without a dog to the north of the heathland where Mr Wrighton had been walking.
The force has said anyone with information should contact them immediately.