A 14-year-old girl is expected to spend weeks in hospital after being viciously attacked by two other girls at a Hastings school.

Adriana Kemp's spine is fractured after two girls punched her multiple times, as she laid on the school field, curling up in pain, TV3 reported.

She is now in Hawke's Bay Hospital where she is expected to spend the next few weeks.

Her mother Moana Hawkins was shocked that Flaxmere College did not call police or an ambulance for her daughter.

"I can't believe anything like this could ever happen at school. You trust your children to go to school and be looked after," she said.

The fight was caught on video by another student, who filmed it with their mobile phone.

"When I saw the video I broke down," Hawkins said. "I wouldn't wish it upon any mother to see what I saw."

She found out about her daughter's attack when a text was sent explaining she had been gang-bashed.

Hawkins rushed to the school, where she asked staff if they had called the police.

"They said 'No we can't do it' so I had to do it," she said. Hawkins also said she asked the school to call an ambulance, but they suggested she should take her daughter to the doctors.

The school said an ambulance wasn't called as the family arrived soon after the incident occurred and told the school they would take her to the hospital.

Flaxmere College principal Louise Anaru said bullying and fighting was a "national issue", when asked if it was a problem at the school.

"Certainly while we had some incidents at the beginning of the year, these decreased markedly in term 2 and 3 and there were none apart from this incident in term 4," she told TV3.

Three girls have been expelled from the school for their involvement in the attack.

Hawkins said her daughter would not be returning to the school and instead of spending her holidays with her grandfather in Australia, she would now be spending them in a hospital bed instead.