Detectives investigating the murder of Joanna Yeates launched a national campaign on Facebook today to appeal for witnesses.
Avon and Somerset Police have placed an advert on the popular social networking site, appealing for help, in the hope of catching the landscape architect's killer.
The 25-year-old's snow-covered body was found on Christmas morning by a couple walking their dogs just three miles from her home in the Clifton area of Bristol.
Detective Chief Inspector Phil Jones, who is leading the murder investigation, said: "The majority of people these days are spending time on Facebook and other social networking sites.
"This has become part of everyday routine for many people.
"This advert allows us to point people to special features on our website with all the latest information, it allows them to contact the incident room direct online rather than calling in.
"I would once again urge anyone who may have not contacted my team and may have information that could help this inquiry to contact us. Let us decide if this information is significant."
Meanwhile, crime scene investigators were at Miss Yeates's flat today, using advanced forensic techniques to examine the scene.
There was a sign outside the building in Canynge Road saying "Do not enter, dangerous chemicals."