The ‘indecent’ event took place around 11am Wednesday outside the female students’ hall, said Principal Prof Sirajul Islam. The authorities have ordered male students to evacuate halls by 1pm and female students by 3pm.

But, he would not say what kind of ‘indecent’ incident took place and for what reason.

“The girls came to me with a charter of demand. I assured them of meeting their demands and told them to go back to their hall but then the indecent incident happened outside the hall,” he said.

Witnesses said IHT students cordoned off the principal’s room around 10:30am protesting against hassles created by outsiders and leaders of local Chhatra League, the student wing of the ruling Awami League.

Female activists led the protest and demanded security on the campus.

They got out of the principal’s room following police intervention and gathered outside their hall.

It was then when a group of men led by Chhatra League's IHT unit President Jahid Hossain and Genetal Secretary ‘Tuhin’ broke police barricades and swooped on the female students, according to witnesses.

Five people suffered injuries in the incident. Three of them have been admitted to the Rajshahi Medical College Hospital.

Chhatra League activists tried to assault the female protesters but police barred them, said Rajparha police OC Hafizur Rahman Hafiz.

“They left the campus on being chased by police. Additional police have been deployed at the scene to avert further untoward situation," he added.

Nadira, a Chhatra League activist who joined the demonstration, said Jahid and Tuhin put a lock outside the female students’ hall to stop them going to a programme of the Chhatra League Rajshahi unit.

“They assaulted two female Chhatra League activists and kept on harassing other female students. The demonstration outside the hall was held to protest against these incidents,” she said.