One Saiful Islam along with a group of youths kidnapped the girl by tying a cloth around her face as she was coming out of her house on the night of June 17, as per the FIR lodged by her relatives on June 20.
Threatening to kill her, they gang-raped her till she fell unconscious before abandoning her near her house, the FIR said.
The girl was recovered there next morning in an unconscious state, it said.
The All Assam Minorities Students Union (AAMSU) Barpeta district unit secretary Maniruj Zamman has demanded "the criminals be punished severely. Otherwise we will start an agitation.