"Friendship bullying" is rife among female high school students with nearly half of Kiwi girls saying they have been bullied by their mates.
Research from the University of Auckland has revealed girls are just as likely to be picked on by their friends as by their enemies.
Researcher Dr Ro Lange said 44 per cent of the 1300 Year 10 girls involved in the study had been bullied by friends and more than 85 per cent had experienced at least one type of bullying such as being ignored or excluded.
Dr Lange, who is also a school counsellor, said there were two distinct types of friendship bullying.
Group bullying involved a group ostracising one member; triadic group bullying involved a third person befriending two best friends and leading to an "awful tug of war" that "just devastates the people involved".