Sources said an employee of the faculty dean office saw a packet of sweetmeat behind teachers' lounge at noon and informed the authorities.

On information, Shahbagh police reached the spot and recovered four cocktails from the packet and sent them to Shahbagh Police Station.

Cocktail explosions, their recoveries from different places of the university and gunshots firing have become common since September this year, foiling authorities' repeated attempts to maintain law and order on the campus.

Two main student bodies, BNP-backed Jatiyatabadi Chhatra Dal (JCD) and Awami League-backed Bangladesh Chhatra League, blame each other for exploding cocktails and firing gunshots.

A number of cocktails were recovered from university's Modhu's Canteen allegedly kept by JCD in October.