Police have arrested a Chhatra League leader at Jahangirnagar University over the alleged rape of a woman after trapping her husband in a residential hall of the university.

They arrested three others for assisting the Chhatra League leader.

The key suspect was arrested on Sunday morning from Savar after the incident took place near the Mir Mosharraf Hossain Hall at 9:30 pm on Saturday, said Police Superintendent Abdullahil Kafi.

The key suspect, Mostafizur Rahman, is a student of the 2015-16 session at the International Relations Department. A former secretary of international relations affairs at the JU wing of Chhatra League, Mostafizur is a resident of Mir Mosharraf Hossain Hall. He is known as a follower of Chhatra League leader Aktaruzzaman Sohel.

Another suspect in the rape, Mamun, is an outsider to the campus. He used to be a tenant of a house owned by the victim and often came to stay with Mostafizur at his room in block A of the hall.

Mostafizur and another campus Chhatra League leader Murad Hossain lived in room No. 317.

Jahangirnagar University Chhatra League have expelled Mostafizur over the incident. However, some other Chhatra League leaders were blamed for assisting the suspects to flee by breaking the entrance locked by the university authorities.

The victim said her house was in Ashulia's Jirani. Their tenant, Mamun, brought her husband to visit the Jahangirnagar University campus on Saturday evening.

At one point, her husband said he needed to buy some furniture. Then Mamun said a furniture trader owed him money and the husband could buy from that shop and pay the amount to Mamun.

As her husband wanted her to accompany him to the furniture shop, he called her and asked her to come to the campus. He also asked her to bring some money and some clothes for Mamun as he would stay with Mostafizur for a few days.

Mamun and Mostafizur then trapped the victim's husband at a room in Mir Mosharraf Hossain Hall.

They then took the clothes from the woman when she arrived.

The victim complained that Mamun returned to her and said she should go to the other entrance of the hall, which was near the woods. When she went to meet him, Mamun and Mostafizur dragged her into the woods and raped her.

At least 50 students demonstrated on the Mir Mosharraf Hossain Hall premises when they learnt about the rape.

The authorities locked all four entrances to the hall in an attempt to capture the rapists, but some Chhatra League leaders broke open one entrance and helped the suspects to flee.

As per the CCTV footage, Chhatra League activists Sagar Siddique and Hasan, students of the Department of International Relations, were seen helping the suspects to escape. Another accomplice was Sabbir, a student of the Department of Botany.

Hasan told journalists that he was unaware of the rape incident and all of them broke the locked entrance under orders from JU Chhatra League Vice President Shah Paran.

All suspects were known as followers of JU Chhatra League President Aktaruzzaman Sohel.

Provost of Mir Mosharraf Hossain Hall Prof Sabbir Alam said they were working to identify the offenders based on the CCTV footage and would take action following an investigation.

Mostafizur did not respond when called on his mobile phone. Later it was found switched off.