Detectives investigating the grisly unsolved murder of a grandmother who was bludgeoned to death a year ago have asked all men who visit, work or live in the area to voluntarily attend DNA screening sessions.
Artist Valerie Graves, 55, is believed to have been murdered with a claw hammer in a ground floor bedroom in Smugglers Lane, Bosham, near Chichester, West Sussex, on December 30 last year.
The culprit has not been caught despite a large investigation.
Ms Graves was killed as she house-sat with her sister Jan, mother Eileen and her sister's partner, Nigel Acres, while the property's owners holidayed abroad over Christmas.
More than 9,500 people have been interviewed by police, a £20,000 reward has been offered, a BBC Crimewatch appeal has been made and a limited DNA match of a suspect has been yielded.
Police returned to Bosham today to speak to residents and visitors in an attempt to force a breakthrough.
Detective Superintendent Nick May, of the Surrey and Sussex major crime team, said officers would return to Smugglers Lane and Bosham Lane tomorrow, from 10am to 4pm, to speak to residents and visitors.
Officers also handed out leaflets and put up posters asking "all men aged over 17 who live, work or visit Bosham to help police find Valerie's killer by providing a simple DNA mouth swab and thumbprint" to "enable police to eliminate as many men as possible from the inquiry".
The drop-in sessions will take place at the Millstream Hotel in Bosham between January 21 and 29, February 2 and 7, and February 10 and 15, police said.
Mr May said: "We need the public's help to catch this person before they hurt someone else and to get justice for Valerie and her family."
Last week, Ms Graves's family spoke of their difficulty in coming to terms with the death.
A post-mortem examination revealed Ms Graves suffered significant head and facial injuries.
A 22-year-old man arrested on suspicion of her murder was later released without charge.