London: Joanna Yeates may have been murdered by a friend who became infatuated with her via Facebook, it emerged last night.

Detectives are now tracing dozens of acquaintances linked to her profile on the social networking website.

Police are increasingly convinced the 25-year-old was killed by someone who knew her and was possibly welcomed into her rented flat in Bristol while her boyfriend was away for the weekend.

Planned to be alone

There was no sign of a break-in and Miss Yeates had let it be known to friends that she was planning to be alone that weekend for the first time since the couple moved in together last October.

Earlier this week, police placed an advert on Facebook in an attempt to reach as many witnesses as possible. Now officers are contacting many of the 200 or so people Miss Yeates had listed as friends on her Facebook profile.

Importantly for the police investigation, her ‘security settings' on the site — designed to restrict access by other Facebook users not in that list — were set quite low, meaning almost anyone with a computer had access to her site.

Many of those who police want to interview do not live in Bristol, but have attended social engagements with Yeates and her 27-year-old boyfriend Greg Reardon.

Officers are also re-interviewing close friends in the city and beyond. Many had previously given statements while her disappearance was being treated as a missing person case.

They want to know if someone had taken a particular interest in her whereabouts or if they had mentioned her name a lot.

Yeates and her boyfriend were both keen users of Facebook and after her death the website was used to set up a memorial page.

She had more than 200 friends on Facebook from all sections of her social life including friends from university, the local rowing club, her family home in Hampshire and other connections.

Officers say they are following up 1,000 leads and are making steady progress.