The mother of a "dorm raid" victim at Otorohanga College hostel says her daughter is targeted by bullies largely because she's pretty, and fears her attackers intend to scar her.

The college has launched an inquiry into a series of dorm room attacks on female students, including one in which a girl's head was allegedly smashed through a window.

Otorohanga College Board of Trustees chairwoman Sonya Hetet did not respond to calls from the Waikato Times but told the Waitomo News three hostel students have been stood down from school, and meetings with their families were held this week.

"We have an official disciplinary process that we have to follow which will be carried out this week," she told the Waitomo News. "Until that is completed we can't make any comment on any specifics around the incident whatsoever."

The dorm raids allegedly involve a group of students breaking into a dorm room at night and assaulting another student.

One parent, who asked to remain anonymous, said her 15-year-old daughter was attacked by a group of at least three girls who broke into her dorm room.

"She was asleep and woke up to girls beating her, and what they do is they put sheets around their fists so as they don't leave marks."

She believed her daughter was singled out and bullied because she was pretty. "We get a lot of comments about how stunning she is from many people, but they fail to realise this is causing her more pain than you would believe.

"She doesn't go looking to start trouble. It's not her fault if boys like her."

The dorm raid happened during her first two weeks at the school and she understood two other girls were targeted on the same night. In the latest – and most violent – incident two weeks ago, a girl allegedly had her head smashed through a window.

The mother said her daughter was targeted on her first day at the college and faced daily verbal and physical abuse, as well as threats by text message and on Facebook.

It was the third school where her daughter had encountered this kind of bullying, but it had "never been this extreme". The ordeal had "rattled" her daughter, who is too afraid to return to the hostel, and it was also taking its toll on the family.

She said the school had failed to resolve the issue and she wanted the bullies removed from school.

Hamilton Abuse Intervention Project manager Lila Jones said violence and bullying among young people had increased steadily, and it was no surprise that girls were the main perpetrators in this case.

"Girls are still more likely to use emotional and psychological abuse than boys; however, we are seeing an increase in physical bullying among girls – whether that is to impress boyfriends or other girls, we can't say."

She said looks, good or bad, were irrelevant, and could not to be used to explain why bullies target a victim.

"We need to stay with the total non-acceptance of such violence, no matter what excuses or explanations people may give."

Otorohanga police Sergeant Andy Conners said they were working with the school. Police believed there were two offenders and a witness. All would be dealt with by Youth Aid.

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