Researchers have identified six different types of killers who turn to Facebook to lure their victim or otherwise use the social networking site in their crimes.
The researchers analysed cases of homicide in which the social networking site Facebook had been reported by the media as a significant factor.
The researchers found 48 cases of "Facebook murder" from around the world between 2008 and 2013 and identified six different types of killers.
They are reactors, informers, antagonists, fantasists, predators or imposters.
A reactor reacts to content posted on Facebook by attacking the victim face to face, researchers explained.
This may be immediately after viewing the content that makes them angry or there may be a time delay in which they revisit the content and ruminate over its meaning.
The informer uses Facebook to inform others that they intend to kill the victim, that they have killed the victim, or both. Informers use Facebook as a way of demonstrating their control over the victim and the situation.
An antagonist engages in hostile exchanges on Facebook that escalate into face to face fatal violence. Antagonists may seek to introduce a physical advantage when the conflict goes offline through arming themselves with weapons.
A fantasist uses Facebook to perform or indulge in a fantasy. For fantasists, the line between fantasy and reality has become increasingly blurred and the homicide may be a way of maintaining the fantasy or preventing others from discovering the deception.
A predator creates and maintains a fake profile to lure a victim and meet them offline. They may draw upon the information available on the victim's profile to identify and exploit vulnerabilities to establish grounds upon which to develop a relationship.
An imposter posts in the name of someone else. This could be the victim in order to create the illusion they are still alive or another person to gain access to and monitor the victim's profile.
"We had been coming across references to 'Facebook Murder' in the media over the past few years but there had been no research in this area," said lead researcher Dr Elizabeth Yardley from the Centre of Applied Criminology at Birmingham City University.
"We wanted to see whether homicides in which Facebook was reported to have been involved were any different to other homicides and found that on the whole they are not - victims knew their killers in most cases, and the crimes echoed what we already know about this type of crime," Yardley said.
Yardley urged that social networking sites should not be blamed for these crimes.
"Facebook is no more to blame for these homicides than a knife is to blame for a stabbing - it's the intentions of the people using these tools that we need to focus upon," she added.
The study was published in the international peer-reviewed Howard Journal of Criminal Justice.
