The two men bragged about what they were doing on Instagram.
Bosham: Detectives Start Door-To-Door DNA Screening
Detectives investigating the murder of Valerie Graves will be knocking on doors next week and asking men in Bosham to volunteer their DNA.
Hundreds of men have already provided DNA samples voluntarily to police who are carrying out screening in an attempt to find the grandmother's killer.
Since January, police have asked all men aged over 17 who live, work or visit Bosham to provide a DNA sample and a thumbprint to eliminate them from the inquiry.
Valerie Graves, 55, was found dead in the bedroom of a house in Smugglers Lane, Bosham, West Sussex, on December 30, 2013, where she had been house-sitting during the Christmas period. She is believed to have been bludgeoned to death
She was staying in the house with her sister Jan, mother Eileen and her sister's partner, Nigel Acres, while the property's owners holidayed abroad over the Christmas period, Sussex Police said.
The mother-of-two's killer still remains at large despite a £20,000 reward being offered by police, a Crimewatch appeal being made and 9,500 people being interviewed in relation to the investigation.
Forensic scientists have obtained a limited DNA profile for the murder suspect, which although not suitable for a search on the National DNA Database, indicates the suspect is male.
Detective Superintendent Nick May of Surrey and Sussex major crime team said: "We want to thank all those men who attended the voluntary sessions in Bosham, Fishbourne and Chichester over the three-week session to give their DNA. The response has been positive.
"We still need those men who have not come forward to do so. We will be doing house-to-house inquiries and knocking on doors during a week of action from Monday April 6 to April 12 asking those who have not given their DNA to consider doing so.
"If we don't get a reply we will also be sending out further letters asking them to attend Chichester police station to give their DNA.
"We have to be tenacious in our efforts to catch the killer. But we do understand that this is an entirely voluntary process and there is no compulsion for anyone to co-operate with us. We simply want to do the best we can for Valerie's family and for the community in bringing the killer to justice."
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