Police and witnesses said the trouble began at around 1:00am when JCD activist Parvez, also a third year student, was observing his birthday playing music loudly in his room on the first floor of the hostel.

Some ICS activists, who were studying in the adjoining rooms, protested playing of music in high volume. The protest resulted in an altercation between the ICS and JCD men.

At one stage, the Chhatra Dal and Shibir activists locked in a clash, leaving 15 injured from both sides.

Of the injured, Mahibul Akhter, Saiful Islam, Mashiur Rahman, Abdul Momen and JCD leader Abdul Matin were admitted to Chittagong Medical College and Hospital (CMCH) while others given first aid.

Sources said 15 rooms of the hostel were ransacked and a motorbike belonging to a Shibir leader was set ablaze during the clash that continued for an hour.

On information, Panchlaish police rushed to the spot and brought the situation under control at about 2:30am.

The CMC authorities formed a four-member committee, headed by Professor Badrul Alam of the Paediatric Department, to probe the incident.