Cyberstalking is now more common than face-to-face harassment with many victims finding themselves pursued by complete strangers online, says a study.

The study, the first of its kind to look at the extent and effect of cyberstalking in social networking sites, email and mobile phones, has revealed the profile of perpetrators to be different from those who pursue victims face-to-face.

Dr Emma Short of at Bedford University, lead author of the study, said the crime was not taken as seriously as it should be, 'The Daily Telegraph' reported.

She said: "There is a lack of understanding of the impact of this behaviour. One of the biggest questions was, 'Is there psychological harm?' Worryingly, a third experienced this. Not just stress, but a clinical record of psychological harm.

"There have been threats to kill. They give the impression that they know where their victims live and can get at them physically. There is a lot of damage to or loss of reputation, people being compromised by false allegations.

"I spoke to a teacher who was followed through chat rooms and the net by someone claiming to have met him through a child porn site. He had a very supportive head, but it went on for several years. He never found out who or what their intention was."

The study found that nearly 40 per cent of cyberstalking victims are men, in contrast to past studies which have identified women as much more at risk from face-to-face stalking.

Most of the victims surveyed were aged 20 to 39, although ages ranged from 14 to 74, with teenagers reporting social networking sites as the environment in which they were most likely to be harassed.

According to Echo the pattern of harassment is different between male and female victims, with men targeted by strangers more than women.

Around 37 per cent of men were stalked by a stranger, compared with 23 per cent of women. Only 4 per cent reported being stalked by a former partner, compared with victims of face-to-face stalking, where around half are former partners.

The largest category of all victims where the perpetrator was a stranger did not know where they had come from, how they were targeted and never found the indentities of those who pursued them, the survey found.