The police also picked up four students -- Moinul Islam, Tutul, Shahinul Haq and Golam Rasul Bhuiyan.

Sources and witnesses said the students were holding a rally in front of the Academic Building at around 10:30am demanding that their department be brought under the social science faculty.

Although the rally was peaceful, a police team led by Inspector Abdul Matin of CU police camp went into action, reportedly at the directive of CU Proctor Dr Didarul Alam Chowdhury, and picked up one of the agitating students, sources said.

When the students urged the inspector to release their fellow student, he misbehaved with them and warned them of "dire consequences", they said.

The students then started hurling stones at the microbus of the police who resorted to baton charge, leaving 15 students injured. The police also picked up three more students.

The students were not released as of 6:00pm yesterday.

The proctor was not available for comments despite repeated attempts to contact him over phone.

The students will form a human chain in front of CU Shaheed Minar tomorrow and submit a memorandum to the vice-chancellor on Sunday to press home their demand.