SIX months ago, a killer struck on a quiet North Yorkshire roadside. David Williamson was bludgeoned from behind and left to die just yards from his home in Sutton-on-the-Forest.

This cowardly and savage attack ended the life of "a loving, kind and gentle man". It devastated his family. And it shocked the seemingly peaceful villages of Sutton-on-the-Forest and Huby.

For detectives, this has proved to be an intractable case. They have so little to work with.

There was no obvious motive. At first it was assumed that Mr Williamson had been the victim of an accident, so unlikely did murder seem.

Once the true cause of his death was established, police were hampered by a lack of witnesses. Mr Williamson was found on a path next to a quiet road on a Sunday night; no one saw him after he left the Star Inn at Huby until he was found, unconscious, at 5.30am.

Without a motive or witnesses, it has proved very difficult to identify potential suspects. There has been no suggestion that this quiet man had made any enemies. Even the leads brought in by a Crimewatch reconstruction have yet to result in anyone being charged.

This lack of significant progress is intensely frustrating for the police officers who have dedicated themselves to bringing Mr Williamson's murderer to justice. And it prolongs the agony for his family, who remain confounded as to why someone would kill him.

Police resources are stretched. The mass DNA screening programme now underway is expensive and time-consuming. Meanwhile, North Yorkshire police have had to devote manpower to another murder, of Michael Brolly in York city centre.

Detectives on the Williamson case today reaffirmed their commitment to solve this crime. They still believe someone is withholding information that could help lead them to the killer. We urge anyone who knows anything to report it to police. Until the murderer is apprehended, they are free to strike again.

Updated: 12:20 Wednesday, September 26, 2001