Ten people have been arrested after dozens of schoolgirls were beaten with sticks and iron rods by a group of boys in India.

The 34 girls, aged between 10 and 16, were playing on the grounds of their boarding school in the north-eastern Indian state of Bihar on Saturday when they caught a group of boys sneaking in.

The boys, who were of a similar age, allegedly shouted obscene comments and sexually harassed the girls, forcing them to kick them out.

The 34 schoolgirls were attacked by a mob of boys and their mothers after they rejected their advances, kicking the boys out of their school grounds. (Reuters)

The boys later returned with a group of about 20 other people who were armed with bamboo sticks and iron rods.

According to police, the boys’ mothers and neighbours were also among the mob.

“They dragged us by our ponytails, assaulted us with sticks, kicked and punched,” one of the students told The Guardian.

“We were unarmed and had nothing to protect us. I saw many of my friends lying on the ground crying with pain,” she said.

All 34 girls were treated in hospital for their injuries.

Beaten with iron rods and bamboo sticks, many of the girls suffered internal injuries. (Reuters)

“Seven to eight children remain here and they are all stable. They have swelling and external injuries, no one has any broken bones of internal injuries,” Doctor Prakash Kumar told Reuters.

Four women are among those arrested so far.

The attack sparked angry protests with residents taking to the streets of the township in protest against the attack on Sunday, calling for girls in state-run institutions to be protected.

The school re-opened yesterday amid enhanced security precautions.

India is the world's most dangerous country for women due to a high risk of sexual violence and being forced into slave labour.